Love蛋撻君 2022-07-28 07:51

（1）5b(2a-b)3+15(b-2a)2

=5b(2a-b)3+15(2a-b)2

=5(2a-b)2[b(2a-b)+3]

=5(2a-b)2(2ab-b2+3)

(2)(2a+3b)2-36(a-2b)2

=(2a+3b)2-(6a-12b)2

=(2a+3b+6a-12b)(2a+3b-6a+12b)

=(8a-9b)(15b-4a)

(3)3x2-2x-8

=(3x+4)(x-2)

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