Solve by making a u-substitution
-$x^{6}+26 x^{3}-27=0$
A) $\{-3,1\}$.
B) $\{-3,-1\}$
C) $\{3,-1\}$.
D) $\{3,1\}$

Name: Solve by making a u-substitution -$x^{6}+26 x^{3}-27=0$ A) $\{-3,1\}$. B) $\{-3,-1\}$ C) $\{3,-1\}$. D) $\{3,1\}$
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Question

Quizplus · Accepted Answer

By substituting $u = x^3$, the equation becomes $u^2 + 26u - 27 = 0$, which factors to $(u + 27)(u - 1) = 0$, giving $u = -27$ and $u = 1$. Substituting back $x^3 = u$, we find $x^3 = -27$ gives $x = -3$, and $x^3 = 1$ gives $x = 1$.

Solve by Making a U-Substitution - x6+26x3−27=0x^{6}+26 x^{3}-27=0x6+26x3−27=0 A) {−3,1}\{-3,1\}{−3,1} B) {−3,−1}\{-3,-1\}{−3,−1}

Solve by Making a U-Substitution
- $x^{6}+26 x^{3}-27=0$ A) $\{-3,1\}$
B) $\{-3,-1\}$