Question

solve for 1
-------
a+bi
dont you times the top with a-bi

Answer 1

You times the top and bottom by a - bi

Answer 2

1(a - bi)
------------
(a + bi)(a - bi)

Answer 3

a - bi
----------
(a^2 + b^2)

Do you understand the denominator.....
The -abi and the +abi cancel out.
The (bi)(-bi) = -b^2i^2 but i^2 = -1 so you have -b^2(-1) = b^2