If z=4+i, what is 1/z? (in the form a+bi)
1/z =1/(4+i) Multiply both top and bottom by the complex conjugate, z* = 4 - i, 1/z = (4-i)/((4+i)(4-i)) = (4-i)/(16+4i-4i-i2) = (4-i)/17 ans: 4/17 - i/17
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