以知x^2+2xy=3,y^2=2,则代数式3x^2+6xy+y^2的值是A.7 B.9 C.11 D.13

来源:学生作业帮助网 编辑:六六作业网 时间:2024/11/23 07:02:44
以知x^2+2xy=3,y^2=2,则代数式3x^2+6xy+y^2的值是A.7B.9C.11D.13以知x^2+2xy=3,y^2=2,则代数式3x^2+6xy+y^2的值是A.7B.9C.11D.

以知x^2+2xy=3,y^2=2,则代数式3x^2+6xy+y^2的值是A.7 B.9 C.11 D.13
以知x^2+2xy=3,y^2=2,则代数式3x^2+6xy+y^2的值是
A.7 B.9 C.11 D.13

以知x^2+2xy=3,y^2=2,则代数式3x^2+6xy+y^2的值是A.7 B.9 C.11 D.13
选C
3x^2+6xy+y^2
=3(x^2+2xy)+y^2
=3*3+2
=9+2
=11