Q. Rewrite the expression as a product of four linear factors:(x2+5x)2−20(x2+5x)+84Answer:
Recognize Quadratic Form: Let's first recognize that the given expression is a quadratic in form, where the variable is not just x, but (x2+5x). We can rewrite the expression as a quadratic equation:Let u=x2+5x. Then the expression becomes:u2−20u+84
Factor Quadratic Expression: Now, we need to factor the quadratic expression u2−20u+84. To do this, we look for two numbers that multiply to 84 and add up to −20. These numbers are −14 and −6. So we can write the factored form as: (u−14)(u−6)
Substitute Back and Simplify: Next, we substitute back x2+5x for u in each factor to get the expression in terms of x:(x2+5x−14)(x2+5x−6)
Factor First Quadratic Expression: Now, we need to factor each quadratic expression further. Starting with x2+5x−14, we look for two numbers that multiply to −14 and add up to 5. These numbers are 7 and −2. So we can write the factored form as: (x+7)(x−2)
Factor Second Quadratic Expression: Next, we factor the second quadratic expression x2+5x−6. We look for two numbers that multiply to −6 and add up to 5. These numbers are 6 and −1. So we can write the factored form as: (x+6)(x−1)
Combine Linear Factors: Finally, we combine all the linear factors to express the original expression as a product of four linear factors: x + \(7)(x - 2)(x + 6)(x - 1)\