二次函数图像与判别式探究:无根抛物线的几何意义
几何画板及绘图内容加载中,请稍等……
本范例演示如何通过 GeoGebra 构造二次函数 f(x)=ax²+bx+c 的图像,并利用判别式 b²-4ac < 0 验证抛物线在 x 轴上没有交点(即无实根)。核心数学概念包括二次函数的图像特征、判别式的几何含义以及根与函数图像的关系。构造要点:使用 Textfield 命令创建用户输入界面,利用 Sequence 命令生成参数序列,通过 If 条件命令判断判别式正负并显示相应提示信息,涉及参数对象 a、b、c 及函数对象 f 的定义。适合中学数学课程中函数与方程、判别式教学使用,也可作为学生自主探究二次函数性质的互动实验工具。
GeoGebra 命令及参数
Textfield(userCondition) → окноВвода4Sequence(Sequence[Sequence[{i, j, k}, i, -5, 5], j, -5, 5], k, -5, 5) → allArgumentsIf(abs(A3 - A2) ≤ 2, B2, B2 + 1) → B3If(abs(A4 - A3) ≤ 2, B3, B3 + 1) → B4If(abs(A5 - A4) ≤ 2, B4, B4 + 1) → B5If(abs(A6 - A5) ≤ 2, B5, B5 + 1) → B6If(abs(A7 - A6) ≤ 2, B6, B6 + 1) → B7If(abs(A8 - A7) ≤ 2, B7, B7 + 1) → B8If(abs(A9 - A8) ≤ 2, B8, B8 + 1) → B9If(abs(A10 - A9) ≤ 2, B9, B9 + 1) → B10If(abs(A11 - A10) ≤ 2, B10, B10 + 1) → B11If(abs(A12 - A11) ≤ 2, B11, B11 + 1) → B12If(abs(A13 - A12) ≤ 2, B12, B12 + 1) → B13If(abs(A14 - A13) ≤ 2, B13, B13 + 1) → B14If(abs(A15 - A14) ≤ 2, B14, B14 + 1) → B15If(abs(A16 - A15) ≤ 2, B15, B15 + 1) → B16If(abs(A17 - A16) ≤ 2, B16, B16 + 1) → B17If(abs(A18 - A17) ≤ 2, B17, B17 + 1) → B18If(abs(A19 - A18) ≤ 2, B18, B18 + 1) → B19If(abs(A20 - A19) ≤ 2, B19, B19 + 1) → B20If(abs(A21 - A20) ≤ 2, B20, B20 + 1) → B21If(abs(A22 - A21) ≤ 2, B21, B21 + 1) → B22If(abs(A23 - A22) ≤ 2, B22, B22 + 1) → B23If(abs(A24 - A23) ≤ 2, B23, B23 + 1) → B24If(abs(A25 - A24) ≤ 2, B24, B24 + 1) → B25If(abs(A26 - A25) ≤ 2, B25, B25 + 1) → B26If(abs(A27 - A26) ≤ 2, B26, B26 + 1) → B27If(abs(A28 - A27) ≤ 2, B27, B27 + 1) → B28If(abs(A29 - A28) ≤ 2, B28, B28 + 1) → B29If(abs(A30 - A29) ≤ 2, B29, B29 + 1) → B30If(abs(A31 - A30) ≤ 2, B30, B30 + 1) → B31If(abs(A32 - A31) ≤ 2, B31, B31 + 1) → B32If(abs(A33 - A32) ≤ 2, B32, B32 + 1) → B33If(abs(A34 - A33) ≤ 2, B33, B33 + 1) → B34If(abs(A35 - A34) ≤ 2, B34, B34 + 1) → B35If(abs(A36 - A35) ≤ 2, B35, B35 + 1) → B36If(abs(A37 - A36) ≤ 2, B36, B36 + 1) → B37If(abs(A38 - A37) ≤ 2, B37, B37 + 1) → B38If(abs(A39 - A38) ≤ 2, B38, B38 + 1) → B39If(abs(A40 - A39) ≤ 2, B39, B39 + 1) → B40If(abs(A41 - A40) ≤ 2, B40, B40 + 1) → B41If(abs(A42 - A41) ≤ 2, B41, B41 + 1) → B42If(abs(A43 - A42) ≤ 2, B42, B42 + 1) → B43If(abs(A44 - A43) ≤ 2, B43, B43 + 1) → B44If(abs(A45 - A44) ≤ 2, B44, B44 + 1) → B45If(abs(A46 - A45) ≤ 2, B45, B45 + 1) → B46If(abs(A47 - A46) ≤ 2, B46, B46 + 1) → B47If(abs(A48 - A47) ≤ 2, B47, B47 + 1) → B48If(abs(A49 - A48) ≤ 2, B48, B48 + 1) → B49If(abs(A50 - A49) ≤ 2, B49, B49 + 1) → B50If(abs(A51 - A50) ≤ 2, B50, B50 + 1) → B51If(abs(A53 - A52) ≤ 2, B52, B52 + 1) → B53If(abs(A54 - A53) ≤ 2, B53, B53 + 1) → B54If(abs(A55 - A54) ≤ 2, B54, B54 + 1) → B55If(abs(A56 - A55) ≤ 2, B55, B55 + 1) → B56If(abs(A57 - A56) ≤ 2, B56, B56 + 1) → B57If(abs(A58 - A57) ≤ 2, B57, B57 + 1) → B58If(abs(A59 - A58) ≤ 2, B58, B58 + 1) → B59If(abs(A60 - A59) ≤ 2, B59, B59 + 1) → B60If(abs(A61 - A60) ≤ 2, B60, B60 + 1) → B61If(abs(A62 - A61) ≤ 2, B61, B61 + 1) → B62If(abs(A63 - A62) ≤ 2, B62, B62 + 1) → B63If(abs(A64 - A63) ≤ 2, B63, B63 + 1) → B64If(abs(A65 - A64) ≤ 2, B64, B64 + 1) → B65If(abs(A66 - A65) ≤ 2, B65, B65 + 1) → B66If(abs(A67 - A66) ≤ 2, B66, B66 + 1) → B67If(abs(A68 - A67) ≤ 2, B67, B67 + 1) → B68If(abs(A69 - A68) ≤ 2, B68, B68 + 1) → B69If(abs(A70 - A69) ≤ 2, B69, B69 + 1) → B70If(abs(A71 - A70) ≤ 2, B70, B70 + 1) → B71If(abs(A72 - A71) ≤ 2, B71, B71 + 1) → B72If(abs(A73 - A72) ≤ 2, B72, B72 + 1) → B73If(abs(A74 - A73) ≤ 2, B73, B73 + 1) → B74If(abs(A75 - A74) ≤ 2, B74, B74 + 1) → B75If(abs(A76 - A75) ≤ 2, B75, B75 + 1) → B76If(abs(A77 - A76) ≤ 2, B76, B76 + 1) → B77If(abs(A78 - A77) ≤ 2, B77, B77 + 1) → B78If(abs(A79 - A78) ≤ 2, B78, B78 + 1) → B79If(abs(A80 - A79) ≤ 2, B79, B79 + 1) → B80If(abs(A81 - A80) ≤ 2, B80, B80 + 1) → B81If(abs(A82 - A81) ≤ 2, B81, B81 + 1) → B82If(abs(A83 - A82) ≤ 2, B82, B82 + 1) → B83If(abs(A84 - A83) ≤ 2, B83, B83 + 1) → B84If(abs(A85 - A84) ≤ 2, B84, B84 + 1) → B85If(abs(A86 - A85) ≤ 2, B85, B85 + 1) → B86If(abs(A87 - A86) ≤ 2, B86, B86 + 1) → B87If(abs(A88 - A87) ≤ 2, B87, B87 + 1) → B88If(abs(A89 - A88) ≤ 2, B88, B88 + 1) → B89If(abs(A90 - A89) ≤ 2, B89, B89 + 1) → B90If(abs(A91 - A90) ≤ 2, B90, B90 + 1) → B91If(abs(A92 - A91) ≤ 2, B91, B91 + 1) → B92If(abs(A93 - A92) ≤ 2, B92, B92 + 1) → B93If(abs(A94 - A93) ≤ 2, B93, B93 + 1) → B94If(abs(A95 - A94) ≤ 2, B94, B94 + 1) → B95If(abs(A96 - A95) ≤ 2, B95, B95 + 1) → B96If(abs(A97 - A96) ≤ 2, B96, B96 + 1) → B97If(abs(A98 - A97) ≤ 2, B97, B97 + 1) → B98If(abs(A99 - A98) ≤ 2, B98, B98 + 1) → B99If(abs(A100 - A99) ≤ 2, B99, B99 + 1) → B100If(abs(A101 - A100) ≤ 2, B100, B100 + 1) → B101If(abs(A103 - A102) ≤ 2, B102, B102 + 1) → B103If(abs(A104 - A103) ≤ 2, B103, B103 + 1) → B104If(abs(A105 - A104) ≤ 2, B104, B104 + 1) → B105If(abs(A106 - A105) ≤ 2, B105, B105 + 1) → B106If(abs(A107 - A106) ≤ 2, B106, B106 + 1) → B107If(abs(A108 - A107) ≤ 2, B107, B107 + 1) → B108If(abs(A109 - A108) ≤ 2, B108, B108 + 1) → B109If(abs(A110 - A109) ≤ 2, B109, B109 + 1) → B110If(abs(A111 - A110) ≤ 2, B110, B110 + 1) → B111If(abs(A112 - A111) ≤ 2, B111, B111 + 1) → B112If(abs(A113 - A112) ≤ 2, B112, B112 + 1) → B113If(abs(A114 - A113) ≤ 2, B113, B113 + 1) → B114If(abs(A115 - A114) ≤ 2, B114, B114 + 1) → B115If(abs(A116 - A115) ≤ 2, B115, B115 + 1) → B116If(abs(A117 - A116) ≤ 2, B116, B116 + 1) → B117If(abs(A118 - A117) ≤ 2, B117, B117 + 1) → B118If(abs(A119 - A118) ≤ 2, B118, B118 + 1) → B119If(abs(A120 - A119) ≤ 2, B119, B119 + 1) → B120If(abs(A121 - A120) ≤ 2, B120, B120 + 1) → B121If(abs(A122 - A121) ≤ 2, B121, B121 + 1) → B122If(abs(A123 - A122) ≤ 2, B122, B122 + 1) → B123If(abs(A124 - A123) ≤ 2, B123, B123 + 1) → B124If(abs(A125 - A124) ≤ 2, B124, B124 + 1) → B125If(abs(A126 - A125) ≤ 2, B125, B125 + 1) → B126If(abs(A127 - A126) ≤ 2, B126, B126 + 1) → B127If(abs(A128 - A127) ≤ 2, B127, B127 + 1) → B128If(abs(A129 - A128) ≤ 2, B128, B128 + 1) → B129If(abs(A130 - A129) ≤ 2, B129, B129 + 1) → B130If(abs(A131 - A130) ≤ 2, B130, B130 + 1) → B131If(abs(A132 - A131) ≤ 2, B131, B131 + 1) → B132If(abs(A133 - A132) ≤ 2, B132, B132 + 1) → B133If(abs(A134 - A133) ≤ 2, B133, B133 + 1) → B134If(abs(A135 - A134) ≤ 2, B134, B134 + 1) → B135If(abs(A136 - A135) ≤ 2, B135, B135 + 1) → B136If(abs(A137 - A136) ≤ 2, B136, B136 + 1) → B137If(abs(A139 - A138) ≤ 2, B138, B138 + 1) → B139If(abs(A140 - A139) ≤ 2, B139, B139 + 1) → B140If(abs(A141 - A140) ≤ 2, B140, B140 + 1) → B141If(abs(A142 - A141) ≤ 2, B141, B141 + 1) → B142If(abs(A143 - A142) ≤ 2, B142, B142 + 1) → B143If(abs(A144 - A143) ≤ 2, B143, B143 + 1) → B144If(abs(A145 - A144) ≤ 2, B144, B144 + 1) → B145If(abs(A146 - A145) ≤ 2, B145, B145 + 1) → B146If(abs(A147 - A146) ≤ 2, B146, B146 + 1) → B147If(abs(A148 - A147) ≤ 2, B147, B147 + 1) → B148If(abs(A149 - A148) ≤ 2, B148, B148 + 1) → B149If(abs(A150 - A149) ≤ 2, B149, B149 + 1) → B150If(abs(A153 - A152) ≤ 2, B152, B152 + 1) → B153If(abs(A154 - A153) ≤ 2, B153, B153 + 1) → B154If(abs(A155 - A154) ≤ 2, B154, B154 + 1) → B155If(abs(A156 - A155) ≤ 2, B155, B155 + 1) → B156If(abs(A157 - A156) ≤ 2, B156, B156 + 1) → B157If(abs(A158 - A157) ≤ 2, B157, B157 + 1) → B158If(abs(A159 - A158) ≤ 2, B158, B158 + 1) → B159If(abs(A160 - A159) ≤ 2, B159, B159 + 1) → B160If(abs(A161 - A160) ≤ 2, B160, B160 + 1) → B161If(abs(A162 - A161) ≤ 2, B161, B161 + 1) → B162If(abs(A163 - A162) ≤ 2, B162, B162 + 1) → B163If(abs(A164 - A163) ≤ 2, B163, B163 + 1) → B164If(abs(A165 - A164) ≤ 2, B164, B164 + 1) → B165If(abs(A166 - A165) ≤ 2, B165, B165 + 1) → B166If(abs(A167 - A166) ≤ 2, B166, B166 + 1) → B167If(abs(A168 - A167) ≤ 2, B167, B167 + 1) → B168If(abs(A169 - A168) ≤ 2, B168, B168 + 1) → B169If(abs(A170 - A169) ≤ 2, B169, B169 + 1) → B170If(abs(A171 - A170) ≤ 2, B170, B170 + 1) → B171If(abs(A172 - A171) ≤ 2, B171, B171 + 1) → B172If(abs(A173 - A172) ≤ 2, B172, B172 + 1) → B173If(abs(A174 - A173) ≤ 2, B173, B173 + 1) → B174If(abs(A175 - A174) ≤ 2, B174, B174 + 1) → B175If(abs(A176 - A175) ≤ 2, B175, B175 + 1) → B176If(abs(A177 - A176) ≤ 2, B176, B176 + 1) → B177If(abs(A178 - A177) ≤ 2, B177, B177 + 1) → B178If(abs(A179 - A178) ≤ 2, B178, B178 + 1) → B179If(abs(A180 - A179) ≤ 2, B179, B179 + 1) → B180If(abs(A181 - A180) ≤ 2, B180, B180 + 1) → B181If(abs(A182 - A181) ≤ 2, B181, B181 + 1) → B182If(abs(A183 - A182) ≤ 2, B182, B182 + 1) → B183If(abs(A184 - A183) ≤ 2, B183, B183 + 1) → B184If(abs(A185 - A184) ≤ 2, B184, B184 + 1) → B185If(abs(A186 - A185) ≤ 2, B185, B185 + 1) → B186If(abs(A187 - A186) ≤ 2, B186, B186 + 1) → B187If(abs(A189 - A188) ≤ 2, B188, B188 + 1) → B189If(abs(A190 - A189) ≤ 2, B189, B189 + 1) → B190If(abs(A191 - A190) ≤ 2, B190, B190 + 1) → B191If(abs(A192 - A191) ≤ 2, B191, B191 + 1) → B192If(abs(A193 - A192) ≤ 2, B192, B192 + 1) → B193If(abs(A194 - A193) ≤ 2, B193, B193 + 1) → B194If(abs(A195 - A194) ≤ 2, B194, B194 + 1) → B195If(abs(A196 - A195) ≤ 2, B195, B195 + 1) → B196If(abs(A197 - A196) ≤ 2, B196, B196 + 1) → B197If(abs(A198 - A197) ≤ 2, B197, B197 + 1) → B198If(abs(A199 - A198) ≤ 2, B198, B198 + 1) → B199If(abs(A200 - A199) ≤ 2, B199, B199 + 1) → B200If(abs(A201 - A200) ≤ 2, B200, B200 + 1) → B201If(abs(A203 - A202) ≤ 2, B202, B202 + 1) → B203If(abs(A204 - A203) ≤ 2, B203, B203 + 1) → B204If(abs(A205 - A204) ≤ 2, B204, B204 + 1) → B205If(abs(A206 - A205) ≤ 2, B205, B205 + 1) → B206If(abs(A207 - A206) ≤ 2, B206, B206 + 1) → B207If(abs(A208 - A207) ≤ 2, B207, B207 + 1) → B208If(abs(A209 - A208) ≤ 2, B208, B208 + 1) → B209If(abs(A210 - A209) ≤ 2, B209, B209 + 1) → B210If(abs(A211 - A210) ≤ 2, B210, B210 + 1) → B211If(abs(A212 - A211) ≤ 2, B211, B211 + 1) → B212If(abs(A213 - A212) ≤ 2, B212, B212 + 1) → B213If(abs(A214 - A213) ≤ 2, B213, B213 + 1) → B214If(abs(A215 - A214) ≤ 2, B214, B214 + 1) → B215If(abs(A216 - A215) ≤ 2, B215, B215 + 1) → B216If(abs(A217 - A216) ≤ 2, B216, B216 + 1) → B217If(abs(A218 - A217) ≤ 2, B217, B217 + 1) → B218If(abs(A219 - A218) ≤ 2, B218, B218 + 1) → B219If(abs(A220 - A219) ≤ 2, B219, B219 + 1) → B220If(abs(A221 - A220) ≤ 2, B220, B220 + 1) → B221If(abs(A222 - A221) ≤ 2, B221, B221 + 1) → B222If(abs(A223 - A222) ≤ 2, B222, B222 + 1) → B223If(abs(A224 - A223) ≤ 2, B223, B223 + 1) → B224If(abs(A225 - A224) ≤ 2, B224, B224 + 1) → B225If(abs(A226 - A225) ≤ 2, B225, B225 + 1) → B226If(abs(A227 - A226) ≤ 2, B226, B226 + 1) → B227If(abs(A228 - A227) ≤ 2, B227, B227 + 1) → B228If(abs(A229 - A228) ≤ 2, B228, B228 + 1) → B229If(abs(A230 - A229) ≤ 2, B229, B229 + 1) → B230If(abs(A231 - A230) ≤ 2, B230, B230 + 1) → B231If(abs(A232 - A231) ≤ 2, B231, B231 + 1) → B232If(abs(A233 - A232) ≤ 2, B232, B232 + 1) → B233If(abs(A234 - A233) ≤ 2, B233, B233 + 1) → B234If(abs(A235 - A234) ≤ 2, B234, B234 + 1) → B235If(abs(A236 - A235) ≤ 2, B235, B235 + 1) → B236If(abs(A237 - A236) ≤ 2, B236, B236 + 1) → B237If(abs(A238 - A237) ≤ 2, B237, B237 + 1) → B238If(abs(A239 - A238) ≤ 2, B238, B238 + 1) → B239If(abs(A240 - A239) ≤ 2, B239, B239 + 1) → B240If(abs(A241 - A240) ≤ 2, B240, B240 + 1) → B241If(abs(A242 - A241) ≤ 2, B241, B241 + 1) → B242If(abs(A243 - A242) ≤ 2, B242, B242 + 1) → B243If(abs(A244 - A243) ≤ 2, B243, B243 + 1) → B244If(abs(A245 - A244) ≤ 2, B244, B244 + 1) → B245If(abs(A246 - A245) ≤ 2, B245, B245 + 1) → B246If(abs(A247 - A246) ≤ 2, B246, B246 + 1) → B247If(abs(A248 - A247) ≤ 2, B247, B247 + 1) → B248If(abs(A249 - A248) ≤ 2, B248, B248 + 1) → B249If(abs(A250 - A249) ≤ 2, B249, B249 + 1) → B250If(abs(A251 - A250) ≤ 2, B250, B250 + 1) → B251
AI 绘图提示语参考
请绘制一个二次函数图像,包含抛物线、x轴和三个用于输入系数a、b、c的文本框。抛物线应根据输入的系数绘制,当判别式b²-4ac小于0时,抛物线与x轴无交点。构造顺序为:先绘制x轴,再绘制抛物线,最后添加输入框。
以上提示语为根据原始绘图命令整理而来,仅供参考。