Question 34574
5/(3+i)
Multiply numerator and denominator by (3-i) as follows:
[5(3-i)]/[(3+i)(3-i)]
Notice the denominator is in the form (a+b)(a-b)
so the denominator takes on the form a^2-b^2, as follows:
=[5(3-i)]/[3^2 - i^2]
But i^2=-1, as you probably just learned, so you get:
=[5(3-i)]/[9+1]
=[5(3-i)]/10
=(3-i)/2
Cheers,
Stan H.