Question

Phân tích phương pháp hằng đẳng thức

(5a-b)²-(2a+3b)²

Answer 1

\(\left(5a-b\right)^2-\left(2a+3b\right)^2=\left(5a-b-2a-3b\right).\left(5a-b+2a+3b\right)=\left(3a-4b\right)\left(6a+2b\right)=2\left(3a-4b\right)\left(3a+b\right)\)

Answer 2

Ta có: \(\left(5a-b\right)^2-\left(2a+3b\right)^2\)

\(=\left(5a-b-2a-3b\right)\left(5a-b+2a+3b\right)\)

\(=\left(3a-4b\right)\left(7a+2b\right)\)

Answer 3

sorry mk làm lỗi 1 chút \(\left(5a-b\right)^2-\left(2a+3b\right)^2=\left(5a-b-2a-3b\right)\left(5a-b+2a+3b\right)=\left(3a-4b\right)\left(7a+2b\right)\)