Câu hỏi của Mắt Ếch

Question

-2,5ab.(-2a2+3b2) =...............................

-2x3(3x+0,5x2-7x3-2)=.........................

(x3-2x2+3x-5)(-xy)=..............................

($\dfrac{-1}{2}$x2y)(3x3-$\dfrac{2}{7}$x2-\(\...

Aki Tsuki · Accepted Answer

$a$) $-2,5ab\left(-2a^2+3b^2\right)=5a^3b-7,5ab^3$

b) $-2x^3\left(3x+0,5x^2-7x^3-2\right)$

$=-6x^4-1x^5+14x^6+4x^3$

c/ $\left(x^3-2x^2+3x-5\right)\left(-xy\right)$

$=-x^4y+2x^3y-3x^2y+5xy$

d/ $\left(-\dfrac{1}{2}x^2y\right)\left(3x^3-\dfrac{2}{7}x^2-\dfrac{4}{5}x+8\right)$

$=-\dfrac{3}{2}x^5y+\dfrac{1}{7}x^4y+\dfrac{2}{5}x^3y-4x^2y$Câu trả lời: $a$) $-2,5ab\left(-2a^2+3b^2\right)=5a^3b-7,5ab^3$

b) $-2x^3\left(3x+0,5x^2-7x^3-2\right)$

$=-6x^4-1x^5+14x^6+4x^3$

c/ $\left(x^3-2x^2+3x-5\right)\left(-xy\right)$

$=-x^4y+2x^3y-3x^2y+5xy$

d/ $\left(-\dfrac{1}{2}x^2y\right)\left(3x^3-\dfrac{2}{7}x^2-\dfrac{4}{5}x+8\right)$

$=-\dfrac{3}{2}x^5y+\dfrac{1}{7}x^4y+\dfrac{2}{5}x^3y-4x^2y$

Nguyễn Huy Tú · Answer

$-2,5ab\left(-2a^2+3b^2\right)=5a^3b-7,5ab^3$

$-2x^3\left(3x+0,5x^2-7x^3-2\right)=-6x^4-x^5+14x^6+4x^3$

$\left(x^3-2x^2+3x-5\right)\left(-xy\right)=-x^4y+2x^3y-3x^2y+5xy$

$\left(\dfrac{1}{2}x^2y\right)\left(3x^3-\dfrac{2}{7}x^2-\dfrac{4}{5}x+8\right)$

$=\dfrac{-3}{2}x^5y+\dfrac{1}{7}x^4y+\dfrac{2}{5}x^3y-4x^2y$Câu trả lời: $-2,5ab\left(-2a^2+3b^2\right)=5a^3b-7,5ab^3$

$-2x^3\left(3x+0,5x^2-7x^3-2\right)=-6x^4-x^5+14x^6+4x^3$

$\left(x^3-2x^2+3x-5\right)\left(-xy\right)=-x^4y+2x^3y-3x^2y+5xy$

$\left(\dfrac{1}{2}x^2y\right)\left(3x^3-\dfrac{2}{7}x^2-\dfrac{4}{5}x+8\right)$

$=\dfrac{-3}{2}x^5y+\dfrac{1}{7}x^4y+\dfrac{2}{5}x^3y-4x^2y$

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