What is the following product?
(xsqrt7-3sqrt8)(xsqrt7-3sqrt8)
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Answer:
7x^2 -12x(sqrt 14) + 72
Step-by-step explanation:
Use foil and you get
x^2(7) - (3x(sqrt56))+(-3x(sqrt56))+ 9(8)
= The inner terms simplify to -6x(sqrt14) + (-6x(sqrt14)) = -12x(sqrt14)
so answer is
7x^2 -12x(sqrt 14) + 72