Question

a, (5x - 2y)(x² - xy + 1)

b, (x - 2)(x + 2)(\(\dfrac{1}{2}\)x - 5)

c, (x² - 2x + 3)(\(\dfrac{1}{2}\)x - 5)

d, (x² - 5)(x + 3) + (x + 4)(x - x²)

GIÚP MÌNH NHÉ MỌI NGƯỜI, MÌNH ĐANG CẦN GẤP !!

Answer 1

a,(5x-2y)(x²-xy+1)=5x³-5x²+5x-2yx²+2xy²-2y

=5x³-7x²y+2xy²+5x-2y

b,(x-2)(x+2)(\(\dfrac{1}{2}\) x-5)=x²-4.\(\left(\dfrac{1}{2}x-5\right)\)

=\(\dfrac{1}{2}x^3-5x^2-2x+20\)

Answer 2

c,\(\left(x^2-2x+3\right)\left(\dfrac{1}{2}x-5\right)\)

=\(\dfrac{1}{2}x^3-5x^2-1x^2+10x+\dfrac{3}{2}x-15\)

=\(\dfrac{1}{2}x^3-6x^2+\dfrac{23}{2}x-15\)

d,\(\left(x^2-5\right)\left(x+3\right)+\left(x+4\right)\left(x-x^2\right)\)

=\(x^3+3x^2-5x-15+x^2-x^3+4x-4x^2\)

=\(-5x+4x-15\)

=\(-x-15\)

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