问题
解答题
当a=-2,b=3时,求下列代数式的值.
(1)(a+b)(a-b);
(2)a2+2ab+b2.
答案
(1)∵a=-2,b=3,
∴(a+b)(a-b)=(-2+3)(-2-3)=-5;
(2)原式=(a+b)2
=(-2+3)2
=1.
当a=-2,b=3时,求下列代数式的值.
(1)(a+b)(a-b);
(2)a2+2ab+b2.
(1)∵a=-2,b=3,
∴(a+b)(a-b)=(-2+3)(-2-3)=-5;
(2)原式=(a+b)2
=(-2+3)2
=1.