You use the FOIL method for this problem. you should get X^2-25
First, you need to distinguish if this is a permutation or a combination. The difference between the two is the order. In combination, order does not matter. Since there is no any restriction given, we assume this is a combination problem. The equation of determining the number of ways to choose 'r' objects out of total 'n' objects is:
Number of ways = n!/r!(n-r)! = 15!/3!(15-3)! = 455
There are 455 ways.
#9) b^4 - 81 = (b^2)^2 - 9^2 = (b^2+ 9)(b^2- 9)<span>
#5) m^4-1 = (m^2)^2 - 1 = </span>(m^2 + 1)(m^2- 1)<span>
#10) 81x^4-16 = (9x^2)^2 - 4^2
= (9x^2 +4)(9x^2 - 4)
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Answer:
cube or square??
Step-by-step explanation:
