化简求值:[(a+0.5b)²+(a-0.5b)²]×(2a²-0.5b²)a=-3 b=4
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化简求值:[(a+0.5b)²+(a-0.5b)²]×(2a²-0.5b²)a=-3 b=4
化简求值:[(a+0.5b)²+(a-0.5b)²]×(2a²-0.5b²)
a=-3 b=4
化简求值:[(a+0.5b)²+(a-0.5b)²]×(2a²-0.5b²)a=-3 b=4
解[(a+0.5b)²+(a-0.5b)²]×(2a²-0.5b²)
=[a^2+b^2/4+ab+a^2+b^2/4-ab]×(2a²-0.5b²)
=(2a^2+b^2/2)×(2a²-0.5b²)
=(2a^2+0.5b^2)×(2a²-0.5b²)
=(2a^2)^2-(0.5b^2)^2
=4a^4-b^4/4
=4a^4-0.25b^4.
[(a+0.5b)²+(a-0.5b)²]×(2a²-0.5b²)
[a^2+ab+0.25b^2+a^2-ab+0.25b^2]×(2a²-0.5b²)
(2a²+0.5b²)(2a²-0.5b²)
(2a²)^2-(0.5b²)^2
4a^4-0.25b^4