SOLUTION: Please help me solve: 6/i - 8/8-i. Combine and write the answer in standard form.

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Question 125695: Please help me solve: 6/i - 8/8-i. Combine and write the answer in standard form.
Found 2 solutions by stanbon, solver91311:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
6/i - 8/8-i. Combine and write the answer in standard form
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[6(8-i)-8i]/[i(8-i)]
= [48-14i]/[8i+1]
Multiply numerator and denominator by (1+8i) to get:
= [2(24-7i)(1-8i)]/(64+1)
= [2(24-56-199i]/65
= (-64+398i)/65
= (-64/65)+ (398/65)i
=========================
Cheers,
Stan H.

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!
6%2Fi+-+8%2F%288-i%29.

The first thing to do is rationalize the denominators, i.e. get the i out of each denominator and then you will be able to find a LCD to allow you to add the fractions.

The first fraction is easy, you just multiply by i%2Fi, giving you -6i%2F1 (remember i%5E2=-1)

The other fraction requires you to remember the factorization of the difference of two squares. a%5E2-b%5E2=%28a%2Bb%29%28a-b%29. Using this, we could multiply the denominator of the second fraction, 8-i by its conjugate 8%2Bi to obtain 8%5E2-i%5E2=64%2B1=65, but to do that we also have to multiply the numerator by the same thing. The result is that the second fraction looks like-%288%288%2Bi%29%29%2F65

Putting it all together we get -%286i%2F1%29-%288%288%2Bi%29%29%2F65

65 is clearly the LCD, so

%28-390i-64-8i%29%2F65=red%28%28-64%2F65%29-%28398i%2F65%29%29