Q4 of 108 Page 46

The product of two expressions is (x – 7) (x2 + 8x + 12). If the HCF of these expressions is (x + 6) then find their LCM.

Product = (x – 7) (x2 + 8x + 12)

= x3 + 8x2 + 12x – 7x2 – 56x – 84


= x3 + x2 – 44x - 84


The LCM = Product / HCF


= (x3 + x2 – 44x - 84) / (x + 6)


The division is as follows:



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