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Not the value of x

Algebra Level 3

If \( \sqrt{ x - 1 } - \sqrt{ x + 1 } + 1 = 0 \) , then \( 4x \) = ?

0 \[ \frac{5}{4} \] \[ \frac{1}{4} \] \[ 4 \sqrt{-1} \] 5 4

Excel in math and science

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by Sakanksha Deo

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