Q. Rewrite the expression as a product of four linear factors:(12x2+11x)2−20(12x2+11x)+75Answer:
Identify Expression: Let's first identify the expression we need to factor:(12x2+11x)2−20(12x2+11x)+75This is a quadratic in form, where the "variable" is (12x2+11x). We can use the factoring method for a quadratic expression, which is generally of the form a2−2ab+b2=(a−b)2.
Denote Variable: Let's denote A=12x2+11x. Then our expression becomes:A2−20A+75Now we need to find two numbers that multiply to 75 and add up to −20. These numbers are −5 and −15.
Find Multiplying Numbers: We can now rewrite the expression as a squared binomial:A2−20A+75=(A−5)(A−15)Remember that A=12x2+11x, so we substitute back in:(12x2+11x−5)(12x2+11x−15)
Rewrite as Binomial: Now we need to factor each quadratic expression. We start with the first one:12x2+11x−5We look for two numbers that multiply to 12∗(−5)=−60 and add up to 11. These numbers are 15 and −4.
Factor First Quadratic: We can now factor the first quadratic: 12x2+11x−5=(3x−1)(4x+5)
Factor Second Quadratic: Next, we factor the second quadratic:12x2+11x−15We look for two numbers that multiply to 12∗(−15)=−180 and add up to 11. These numbers are 20 and −9.
Combine Factors: We can now factor the second quadratic: 12x2+11x−15=(3x−5)(4x+3)
Combine Factors: We can now factor the second quadratic: 12x2+11x−15=(3x−5)(4x+3) Finally, we combine the factors of both quadratic expressions to express the original expression as a product of four linear factors: (3x−1)(4x+5)(3x−5)(4x+3)
More problems from Find derivatives of using multiple formulae