Simplify the following expressions in the form a+bi

Question

1. (13 − √−25) + (−2 + √−9)

2.(1+7i)(3-2i)

Answer 1

1. (13 − √−25) + (−2 + √−9)

 

=13- √−25 -2 + √−9

 

=11-5i+3i

 

=11-2i

 

 

2.(1+7i)(3-2i)

= 3 -2i +21i -14i²

=3 +19i -(14)(-1)

=3+19i+14

=17+19i