Question

计算:

(1)(-2)²

(2)÷()×(4);

(3)(3+)(3-)-(-1)²;

(4)(+-)(-+).

Answer

（1）12；（2）10；（3）2；（4）2-4

【解析】

根据二次根式的运算法则与整式的乘法法则依次计算即可.

解:(1)(-2)2=(-2)2×()2=12.

(2)÷()×(4)

=1××4×()

=10×

=10.

(3)(3+)(3-)-(-1)2

=32-()2-[()2-2+1]

=9-5-3+2-1

=(9-5-3-1)+2

=2.

(4)(+-)(-+)

=[+(-)][-(-)]

=()2-(-)2

=3-(7-2)

=2-4.