a)\(-x^2\left(x^2-4\right)=-25\left(x^2-4\right)\)
\(\Leftrightarrow-x^2=-25\)
\(\Leftrightarrow x^2=25\)
\(\Leftrightarrow x=\pm5\)
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Các câu hỏi tương tự
Thu gọn các biểu thức sau:
A left|x^2+2right|+left|-3x^2-2right|-left|-2x^2-2right|
B left|2x-3right|-left|3x-2right|-left|4-2xright| với x 5
C left|3x-6right|+left|3x+10right| với -2 x 2
D left|8-3xright|+left|x+2right| với x 2
E left|x-2right|+left|x-4right|+left|x-6right| với x 5
F left|left(x-2right)left(x-4right)right|-left|left(4-xright)left(x-2right)right|
Đọc tiếp
Thu gọn các biểu thức sau:
A = \(\left|x^2+2\right|+\left|-3x^2-2\right|-\left|-2x^2-2\right|\)
B = \(\left|2x-3\right|-\left|3x-2\right|-\left|4-2x\right|\) với x > 5
C = \(\left|3x-6\right|+\left|3x+10\right|\) với -2 < x < 2
D = \(\left|8-3x\right|+\left|x+2\right|\) với x < 2
E = \(\left|x-2\right|+\left|x-4\right|+\left|x-6\right|\) với x < 5
F = \(\left|\left(x-2\right)\left(x-4\right)\right|-\left|\left(4-x\right)\left(x-2\right)\right|\)
rut gon
\(\left(3x-1\right)^2+2\left(9x^2-1\right)+\left(3x+1\right)^2\)
\(\left(x^2-1\right)\left(x+3\right)-\left(x-3\right)\left(x^3+3x+9\right)\)
\(\left(x+4\right)\left(x-4\right)-\left(x-4\right)^2\)
Tìm x: \(\frac{\left(x-2\right)^2}{2}-4\frac{1}{3}\left(x+3\right)^2=\frac{1}{4}\left(x-1\right)\left(x-2\right)-2\left(3x-1\right)\left(2+3x\right)\)
Tìm x: \(\frac{\left(2-3x\right)^2}{3}-\frac{\left(1+2x\right)^2}{2}=\frac{3}{4}-2\left(x-1\right)\left(x+2\right)+x\left(1+x\right)\)
Thu gọn :
a) \(2\left(x^2-3x+5\right)-4\left(x^2+x-1\right)\)
b) \(-5\left(x^2-3\right)+2\left(x-5\right)-4\left(x^2+x-5\right)\)
c) \(\frac{1}{2}\left(2x^2-4x+1\right)-\left(x^2+\frac{1}{2}\right)\)
Tìm x : \(\left(x-3\right)^2-\left(2x+1\right)^2-2\left(x-1\right)\left(x+2\right)=3\left(x-3\right)-\left(4x-1\right)\left(x+2\right)\)
Tìm x: \(3\left(x-2\right)^2-1\frac{1}{4}\left(1+3x\right)^2=1\frac{1}{3}\left(x-1\right)\left(3-x\right)-1\frac{1}{6}x\left(x-3\right)\)
Tìm x: \(\left(2x+1\right)^2-3\left(2-x\right)^2+2\left(x-1\right)\left(x+2\right)=4-2\left(1-x\right)\)
Tìm x: \(3\left(x-2\right)^2-1\frac{1}{4}\left(1+3x\right)^2=1\frac{1}{3}\left(x-1\right)\left(3+x\right)-1\frac{1}{6}x\left(x-3\right)\)