(a+b)(a-2b)-(2a-b)(-2a-b)化简后等于多少?明天之前
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(a+b)(a-2b)-(2a-b)(-2a-b)化简后等于多少?明天之前
(a+b)(a-2b)-(2a-b)(-2a-b)化简后等于多少?
明天之前
(a+b)(a-2b)-(2a-b)(-2a-b)化简后等于多少?明天之前
(a+b)(a-2b)-(2a-b)(-2a-b)
=a^2-ab-2b^2-[(-b)^2-(2a)^2]
=a^2-ab-2b^2-b^2+4a^2
=5a^2-ab-3b^2.
=a^2-ab-2b^2-b^2+4a^2
=5a^2-3b^2-ab
5a^2-ab-3b^2
(a+b)(a-2b)-(2a-b)(-2a-b)
=(a²-2ab+ab-2b²)-(-4a²-2ab+2ab+b²)
=(a²-ab-2b²)-(-4a²+b²)
=a²-ab-2b²+4a²-b²
=5a²-ab-3b²
3a^2-ab+2b^2
5a^2-ab-3b^2
=a^2-ab-2b^2-b^2+4a^2
=5a^2-3b^2-ab
(a+b)(a-2b)-(2a-b)(-2a-b)
=a^2-ab-2b^2-[(-b)^2-(2a)^2]
=a^2-ab-2b^2-b^2+4a^2
=5a^2-ab-3b^2.
(a+b)(a-2b)-(2a-b)(-2a-b) <...
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5a^2-ab-3b^2
=a^2-ab-2b^2-b^2+4a^2
=5a^2-3b^2-ab
(a+b)(a-2b)-(2a-b)(-2a-b)
=a^2-ab-2b^2-[(-b)^2-(2a)^2]
=a^2-ab-2b^2-b^2+4a^2
=5a^2-ab-3b^2.
(a+b)(a-2b)-(2a-b)(-2a-b)
=(a²-2ab+ab-2b²)-(-4a²-2ab+2ab+b²)
=(a²-ab-2b²)-(-4a²+b²)
=a²-ab-2b²+4a²-b²
=5a²-ab-3b²
3a^2-ab+2b^2
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(a+b)(a-2b)-(2a-b)(-2a-b)
=(a+2b-b)(a-2b)+(4a2-b2)
=(a2-4b2)-b(a-2b)+(4a2-b2)
=5a2-5b2-ab+2b2
=5a2-3b2-ab