Đáp án:
`4b(4a-3b)`
Giải thích các bước giải:
`4(2a-b)^2-16(a-b)^2`
`=[2(2a-b)]^2-[4(a-b)]^2`
`=[2(2a-b)+4(a-b)][2(2a-b)]-4(a-b)]`
`=(4a-2b+4a-4b)(4a-2b-4a+4b)`
`=(8a-6b).2b`
`=2.(4a-3b).2b`
`=4b(4a-3b)`
Áp dụng HĐT:`A²-B²=(A+B)(A-B)`
`+)`Nếu đề là :`4)` `(2a-b)^2-16(a-b)^2``=(2a-b)^2-[4(a-b)]^2``=(2a-b)^2-(4a-4b)^2``=(2a-b+4a-4b)(2a-b-4a+4b)``=(6a-5b)(-2a+3b)`____________________________________ `+)` Nếu đề là :`4(2a-b)^2-16(a-b)^2``=[2(2a-b)]^2-[4(a-b)]^2``=(4a-2b)^2-(4a-4b)^2``=(4a-2b+4a-4b)(4a-2b-4a+4b)``=2b(8a-6b)``=4b(4a-3b)`
Help em nha!!!!!!!!!!!!!!!!!!!!!!!!!!!
Tìm các giá trị x nguyên để tại đó giá trị của mỗi biểu thức sau là một số nguyên: e. E = (4/x^2-4x + 1/x+2) : (2x-4-x^2)/2x^2+4x
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giúp mình nha câu hỏi mình để trong phần bình luận nha
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