How do you multiply #(15+3i)(4-15i)#? Precalculus Complex Numbers in Trigonometric Form Multiplication of Complex Numbers 1 Answer Gerardina C. Aug 24, 2016 #105-213i# in the standard form Explanation: First, let's multiply term by term to have: #60-225i+12i-45i^2# Then, since #i^2=-1#, you have #60-213i+45# #105-213i# in the standard form Answer link Related questions How do I multiply complex numbers? How do I multiply complex numbers in polar form? What is the formula for multiplying complex numbers in trigonometric form? How do I use the modulus and argument to square #(1+i)#? What is the geometric interpretation of multiplying two complex numbers? What is the product of #3+2i# and #1+7i#? How do I use DeMoivre's theorem to solve #z^3-1=0#? How do I find the product of two imaginary numbers? How do you simplify #(2+4i)(2-4i)#? How do you multiply #(-2-8i)(6+7i)#? See all questions in Multiplication of Complex Numbers Impact of this question 1839 views around the world You can reuse this answer Creative Commons License