Question

Tìm x biết :

\(x^4:9=9\)\(\)

\(x^2-30=6\)

\(x^2:10=10\)

Answer 1

a,\(x^4:9=9\\ \Leftrightarrow\orbr{\begin{cases}x=1\\x=-1\end{cases}}\)

b,\(x^2-30=6\\ \Leftrightarrow x^2=36\Leftrightarrow\orbr{\begin{cases}x=6\\x=-6\end{cases}}\)

c,\(x^2:10=10\Leftrightarrow x^2=\orbr{\begin{cases}x=1\\x=-1\end{cases}}\)

Answer 2

x⁴ : 9 = 9

x⁴ = 9 . 9

x⁴ = 81

x⁴ = 3⁴

=> x = 3

x² - 30 = 6

x² = 6 + 30

x² = 36

x² = 6²

=> x = 6

x² : 10 = 10

x² = 10 . 10

x² = 100

x² = 10²

=> x = 10