vì \(x^4+2x^2+1=\left(x^2+1\right)^2\) mà \(x^2\ge0\Rightarrow x^2+1>0\Rightarrow\left(x^2+1\right)^2>0\)với mọi x.Nên x-3=0 .Từ đó suy ra x=3
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Tìm x
a,x^2-11x-26=0
b,2x^2+7x-4=0
c,(x-2)(x-3)+(x-2)-1=0
HELP ME TÍ NX ĐI HK R
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A) 2x³+6x²=x²+3x
B) (2x+5)²=(x+2)²
C) x²-5x+6=0
D) (2x-7)²-6(2x-7)(x-3)=0
E) (x-2)(x+1)=x²-4
G) 2x(2x-3)=(3-2x)(2-5x)
H) (1-x)(5x+3)=(3x-7)(x-1)
F) (x+6)(3x-1)+x+6=0
I) (4x-1)(x-3)=(x-3)(5x+2)
K) (x+4)(5x+9)-x-4=0
H) (x+3)(x-5)+(x+3)(3x-4)=0
Tìm x, biết:
a) 3x(x-1)^2-3x(x-5)-2=0
b)x^3-x^2-x+1=0
c)2x^2 - 5x - 7=0
help me. Mai mik hok.
tìm x:
a) x4+2x3-6x-9=0
b) 4x+\(4\sqrt{2}x^2\)+2x3=0
c) (2x3-3)2-(4x2-9)=0
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Tìm x biết:
a,x^2+2y^2-2xy-2x-2xy+5=0
b,x^2+5y^2-2xy+4x-8y+5
c,y^2+2y+4^x-2^x+1+2=0
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Bài 1: rút gọn a. ( x + 1)^2 - (x - 1)^2 - 3(x + 1)(x - 1)b. 5(x +2)(x -2) - 1/2(6 - 8x)^2 + 17c. (x^2 - 1)^3 - (x^4 + x^2 + 1)(x^2 - 1)d. (x^4 - 4x^2 +9)(x^2 + 3) - (3 + x^2)^3e. (x-3)^3 -(x - 3)(x^2 +3x + 9) + 6(x + 1)^2Bài 2: tìm xa. 25x^2 - 9 0b. (x + 4)^2 - (x + 1) (x -1) 16c. (2x - 1)^2 + (x + 3)^2 - 5(x + 7)(x - 7) 0d. (x + 2)(x^2 - 2x + 4) - x(x^2 + 2) 15e. (x + 3)^3 - x(3x + 1)^2 + (2x + 1)(4x^2 - 2x + 1) 28g. (x^2 - 1)^3 - (x^4 + x^2 + 1)(x^2 -1) 0HELP ME!!!!!!!!
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Bài 1: rút gọn
a. ( x + 1)^2 - (x - 1)^2 - 3(x + 1)(x - 1)
b. 5(x +2)(x -2) - 1/2(6 - 8x)^2 + 17
c. (x^2 - 1)^3 - (x^4 + x^2 + 1)(x^2 - 1)
d. (x^4 - 4x^2 +9)(x^2 + 3) - (3 + x^2)^3
e. (x-3)^3 -(x - 3)(x^2 +3x + 9) + 6(x + 1)^2
Bài 2: tìm x
a. 25x^2 - 9 = 0
b. (x + 4)^2 - (x + 1) (x -1) = 16
c. (2x - 1)^2 + (x + 3)^2 - 5(x + 7)(x - 7) = 0
d. (x + 2)(x^2 - 2x + 4) - x(x^2 + 2)= 15
e. (x + 3)^3 - x(3x + 1)^2 + (2x + 1)(4x^2 - 2x + 1) = 28
g. (x^2 - 1)^3 - (x^4 + x^2 + 1)(x^2 -1) = 0
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tìm x ,biết : ( 8x - 4x^2 -1 ) ( x^2 +2x +1 )= 4(x^2 +x+1 ) ...Please !! Heo mì !!!(Help me !!! )
Tìm x:
\(x^3-x=0\)
\(x^2-2x+x-2=0\)
\(x^2-6x+8=0\)
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tìm x biết: \(2x^2-2x=0\)help me mai HK 1 r