Law of indices : Rule: a^m * a^n = a^m+nTo multiply expressions with the same base, copy the base and add the indices. Lets start with gathering the a's - a^3 and a^2 adding the indices gets a^5Now b's - b^4 * b = b^5 Don't forget the 2 numbers 5*2 = 10 Altogether is simplified to : 10a^5b^4