Câu hỏi của Namiru Ikiou

Question

a) 3x^2(x-1)+(1-x)

b)25-x^2+2xy-y^2

c)x^2+4xy^2

không biết mình có làm đúng như các bn giải ko nên hỏi để cho chắc cảm ơn mấy bn trước

qwerty · Accepted Answer

a) $3x^2\left(x-1\right)+\left(1-x\right)$

$=3x^2\left(x-1\right)+\left(-x+1\right)$

$=3x^2\left(x-1\right)-\left(x-1\right)$

$=\left(3x^2-1\right)\left(x-1\right)$

b) $25-x^2+2xy-y^2$

$=-\left(x^2-2xy+y^2\right)+5^2$

$=-\left(x-y\right)^2+5^2$

$=-\left(x-y+5\right)\left(x-y-5\right)$

c) $x^2+4xy^2$

$=x\left(x+4y^2\right)$Câu trả lời: a) $3x^2\left(x-1\right)+\left(1-x\right)$

$=3x^2\left(x-1\right)+\left(-x+1\right)$

$=3x^2\left(x-1\right)-\left(x-1\right)$

$=\left(3x^2-1\right)\left(x-1\right)$

b) $25-x^2+2xy-y^2$

$=-\left(x^2-2xy+y^2\right)+5^2$

$=-\left(x-y\right)^2+5^2$

$=-\left(x-y+5\right)\left(x-y-5\right)$

c) $x^2+4xy^2$

$=x\left(x+4y^2\right)$

nguyen thi vang · Answer

a) 3x2. (x-1) + (1-x)

$=3x^2\left(x-1\right)-\left(x-1\right)$

$=3x^2\left(x-1\right)-\left(x-1\right).1$

$=\left(3x^2-1\right)\left(x-1\right)$

b) 25 - x2 + 2xy - y2

$=-\left(x^2-2xy+y^2+5^2\right)$

$=-\left(x-y\right)^2+5^2$

$=-\left(x-y+5\right)\left(x-y-5\right)$

c) x2+ 4xy2

$=x\left(x+4y^2\right)$

Chúc bạn học tốt !Câu trả lời: a) 3x2. (x-1) + (1-x)

$=3x^2\left(x-1\right)-\left(x-1\right)$

$=3x^2\left(x-1\right)-\left(x-1\right).1$

$=\left(3x^2-1\right)\left(x-1\right)$

b) 25 - x2 + 2xy - y2

$=-\left(x^2-2xy+y^2+5^2\right)$

$=-\left(x-y\right)^2+5^2$

$=-\left(x-y+5\right)\left(x-y-5\right)$

c) x2+ 4xy2

$=x\left(x+4y^2\right)$

Chúc bạn học tốt !

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