Q. Use the imaginary number i to rewrite the expression below as a complex number. Simplify all radicals. −98
Replace with imaginary unit: Now, we know that −1 is the imaginary unit i, so we can replace that part of the expression.−1×98=i×98
Simplify square root of 98: Next, we simplify 98 by finding the prime factors of 98 and looking for pairs to take out of the square root.98=2×49=2×7×7We can take a pair of 7 out of the square root as 7.98=7×2
Combine i and square root: Now we can combine the i and the simplified square root to get the final complex number.i⋅98=i⋅7⋅2
Write final complex number: Finally, we write the expression as a complex number.i×7×2=7i×2But wait, we made a mistake here. We should have written 7×2 as 7×i×2.
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