Question 116266
125 - 8x cubed 
= 5^3-(2x)^3
= (5-2x)(5^2+5(2x)+(2x)^2)
= (5-2x)(25+10x+4x^2
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54t cubed + 16v cubed 
= 2(27t^3 + 8v^3)
= 2(3t+2v)((3t)2-(3t)(2v)+(2v)^2}
= 2(3t+2v)(9t^2-6tv+4v^2)
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Cheers,
Stan H.