\(x\left(x^2-49\right)=0\\ x\left(x-7\right)\left(x+7\right)=0\\ \left\{{}\begin{matrix}x=0\\x-7=0\\x+7=0\end{matrix}\right.\\ \left\{{}\begin{matrix}x=0\\x=7\\x=\left(-7\right)\end{matrix}\right.\)
\(x\left(x^2-49\right)=0\\ x\left(x-7\right)\left(x+7\right)=0\\ \left\{{}\begin{matrix}x=0\\x-7=0\\x+7=0\end{matrix}\right.\\ \left\{{}\begin{matrix}x=0\\x=7\\x=\left(-7\right)\end{matrix}\right.\)
Tìm x:
49x^3 - x = 0
4x3+26x2+49x-y2+2y+20=0
tìm x,y thuộc Z
tìm x:49x^2-81=0(vận dụng các hằng thức)
tìm x
a/ 2x(x-5)-x(3+2x)=26
b/ 49x2-81=0
thank trước nha
BT9: Tìm x biết
\(9,\left(2x-5\right)^2-\left(x+1\right)^2=0\)
\(10,\left(x+3\right)^2-x^2=45\)
\(11,\left(5x-4\right)^2-49x^2=0\)
\(12,16\left(x-1\right)^2-25=0\)
Tìm x,biết:
a) x^2-36=0
b) (3x-5)^2-(x+6)^2=0
c) (5x-4)^2-49x^2=0
d)4x^3-36x=0
e) 2/3x(x^2-4)=0
Tìm x, biết:
a) 2-x = 2 ( x - 2 ) 3 ; b) 8 x 3 - 72x = 0;
c) ( x - 1 , 5 ) 6 + 2 ( 1 , 5 - x ) 2 = 0; d) 2 x 3 +3 x 2 +3 + 2x = 0;
e) x 3 - 4x- 14x(x - 2) = 0; g) x 2 (x + 1)- x(x + 1) + x(x - 1) = 0.
tìm x:
x^3-49x=0
tìm x
a,x^3+3x^2=4x+12 b,49x^2=(3x+2)^2 c,3x^2(x-5)+12(5-x)=0 d,x^2(x-5)+45-9x=0