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find the value of x if 3^{x2 - 1} = 27/3^{-3x}

A. 4, -1

B. 4, 1

C. -4, -1

D. 4, 1

**Comments**

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from indices,

3^{x2 - 1} = 3^{3}/3^{-3x}

x^{2} - 1 = 3 - (-3x)

x^{2} - 1 = 3 + 3x

x^{2} - 1 - 3 - 3x = 0

x^{2} - 3x - 4 = 0

from factorization method of solving quadratic equation

x^{2} - 4x + x - 4 = 0

(x^{2} - 4x) + (x - 4) = 0

x(x - 4) + 1(x - 4) = 0

(x + 1) (x - 4) = 0

x + 1 = 0

x - 4 = 0

x = -1, 4

**Ans A**

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