Q. Express the radical using the imaginary unit, i.Express your answer in simplified form.±−90=±□
Expressing square roots: Next, we can express the square root of −1 as i and the square root of 90 as the product of its prime factors under the radical.±−1×90=±i×90
Simplifying square root of 90: Now, we simplify the square root of 90 by finding the prime factors of 90 and identifying any perfect squares. 90=2×4545=5×99 is a perfect square (32), so we can take the square root of 9 out of the radical.±i×90=±i×2×5×9
Taking square root of 9 out: We can now simplify the expression by taking the square root of 9 out of the radical, which is 3.±i⋅2⋅5⋅9=±i⋅3⋅2⋅5
Combining constants outside radical: Finally, we simplify the expression by combining the constants outside the radical. ±i×3×2×5=±3i×10
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