Question

Tìm x:
a)x⁴-16x²=0
b)9x²-30x+25=0

Answer 1

\(a,\Leftrightarrow x^2\left(x-4\right)\left(x+4\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}x=0\\x=4\\x=-4\end{matrix}\right.\\ b,\Leftrightarrow\left(3x-5\right)^2=0\Leftrightarrow x=\dfrac{5}{3}\)

Answer 2

a) pt <=> x^2(x - 4)(x + 4) = 0

<=> x = 0 hoặc x = 4 hoặc x = -4

b) pt <=> (3x -5)^2=0

<=> x = 5/3

Answer 3

a: \(x^4-16x^2=0\)

\(\Leftrightarrow x^2\left(x-4\right)\left(x+4\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x=0\\x=4\\x=-4\end{matrix}\right.\)

b: \(9x^2-30x+25=0\)

\(\Leftrightarrow3x-5=0\)

hay \(x=\dfrac{5}{3}\)