How do you multiply #(3x ^ { 2} + 5) ( 7x ^ { 2} + 4)#?

1 Answer
smendyka
Nov 30, 2016

#21x^4 + 47x^2 + 20#

Explanation:

You cross multiply each term in the first parenthesis with each term in the second parenthesis as follows:

#(3x^2*7x^2) + (3x^2*4) + (5*7x^2) + (5*4) ->#

#21x^(2+2) + 12x^2 + 35x^2 + 20 ->#

#21x^4 + (12 + 35)x^2 + 20#

#21x^4 + 47x^2 + 20#

Related questions
Impact of this question
475 views around the world
You can reuse this answer
Creative Commons License