A = -(x + 2)(x - 5) + (x - 1)(x - 2)
A = -x2 + 3x + 10 + x2 - 3x + 2
A = (-x2 + x2) + (3x - 3x) + 10 + 2
A = 12
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Rút gọn:
a) A=(5-x)(5+x)-x(4-x)-25
b) B=(x2+1)(x+1)-(x+1)3
c) C=(x+y-2)2-2(x+y-2)(y+x)+(x+y)2
Bài 1: Rút gọn:
A = \(\dfrac{x}{x-2}+\dfrac{x^2+x-2}{4-x^2}\)
Rút gọn:
a) A= \(\dfrac{x}{x-y}+\dfrac{2y^2}{x^2-y^2}-\dfrac{x}{x+y}\)
b) B= \(\dfrac{x}{x-2}-\dfrac{4x}{x^2-4}-\dfrac{2}{x+2}\)
c) C= \(\dfrac{5}{x+1}-\dfrac{10}{-x^2+x-1}-\dfrac{15}{x^3+1}\)
Rút gọn:
A = \(\dfrac{x+3}{x^2-6x+9}:\left(\dfrac{12-x^2}{x^2-3x}-\dfrac{1}{3-x}+\dfrac{x+3}{x}\right)\)
Rút gọn:
a) A=(5-2x)2-4x(x-5)
b) B= (4-3x)(4+3x)+(3x+1)2
c) C= (x+1)3-x(x2+3x+3)
d) D=(2021x-2020)2-2(2021x-2020)(2020x-2021)+(2020x-2021)
Rút gọn:a) dfrac{3left(x-yright)left(x-zright)^2}{6left(x-yright)left(x-zright)}b) dfrac{6x^2y^2}{8xy^5}c) dfrac{3xleft(1-xright)}{2left(x-1right)}d) dfrac{9-left(x+5right)^2}{x^2+4x+4}e) dfrac{x^2-2x+1}{x^2-1}f) dfrac{8x-4}{8x^3-1}g) dfrac{x^2+5x+6}{x^2+4x+4}k) dfrac{20x^2-45}{left(2x+3right)^2}
Đọc tiếp
Rút gọn:
a) \(\dfrac{3\left(x-y\right)\left(x-z\right)^2}{6\left(x-y\right)\left(x-z\right)}\)
b) \(\dfrac{6x^2y^2}{8xy^5}\)
c) \(\dfrac{3x\left(1-x\right)}{2\left(x-1\right)}\)
d) \(\dfrac{9-\left(x+5\right)^2}{x^2+4x+4}\)
e) \(\dfrac{x^2-2x+1}{x^2-1}\)
f) \(\dfrac{8x-4}{8x^3-1}\)
g) \(\dfrac{x^2+5x+6}{x^2+4x+4}\)
k) \(\dfrac{20x^2-45}{\left(2x+3\right)^2}\)
Bài 2:Tính:
a,(x- 6y) (x+6y)
b,(x-2) (x2 +2x+4)
Bài 3:Rút gọn:
a,(x+1)2 - (x-1)2 - 3 (x+1) (x-1)
b,(x - 1)3 - ( x-1) 3 + 6 (x-1) (x+1)
Rút gọn:
a)2x.(3x-1)-(x-3).(6x+2)
b)(2x-3)2-(1+2x).(2x-1)+3.(2x-3)
c)(x+y-1)2-2.(x+y-1).(x+y)+(x+y)2
Rút gọn:
a) A=(4-x)(16+4x+x2)-(4-x)3
b) B=(3x+2)(9x2-6x+4)-(9x2+6x+4)(3x-2)
c) C=(x+1)(x2-x+1)-x(x+1)2
Rút gọn:
a)(5x-4)(5x+4)-(5x-4)2
b)(5x+3)2-(4x-1)2-(9x2+8)
c)2(x-5y)(x+5y)+(x+5y)2+(x-5y)2