Q. Rewrite the expression as a product of four linear factors:(12x2+5x)2−9(12x2+5x)+14Answer:
Recognize quadratic form: Recognize the given expression as a quadratic in form.The given expression is:(12x2+5x)2−9(12x2+5x)+14This is a quadratic equation in the form of (ax+b)2−c(ax+b)+d, where a=12, b=5, and c=9, d=14.
Substitute variable y: Let y=12x2+5x. We can substitute y for 12x2+5x to make the expression easier to work with. So the expression becomes: y2−9y+14
Factor quadratic expression: Factor the quadratic expression.We need to factor y2−9y+14.To factor, we look for two numbers that multiply to 14 and add up to −9.The numbers that satisfy these conditions are −7 and −2.So we can write the quadratic as:(y−7)(y−2)
Substitute back for y: Substitute back 12x2+5x for y.Now we replace y with 12x2+5x in the factored form:(12x2+5x−7)(12x2+5x−2)
Factor each quadratic further: Factor each quadratic expression further.We need to factor each quadratic expression into two linear factors.Starting with 12x2+5x−7, we look for two numbers that multiply to −84 (12×−7) and add up to 5. These numbers are 7 and −12.So we can write the quadratic as:(3x−7)(4x+1)Similarly, for 12x2+5x−2, we look for two numbers that multiply to −24 (12×−2) and add up to 5. These numbers are −841 and −842.So we can write the quadratic as:−843
Combine linear factors: Combine the linear factors to express the original expression.Now we combine all the linear factors to express the original expression as a product of four linear factors:(3x−7)(4x+1)(3x−2)(4x+1)
Check for repeated factors: Check for repeated factors.We notice that the factor (4x+1) is repeated. So we can write the final expression as:(3x−7)(4x+1)2(3x−2)
Verify full factorization: Verify that the expression is fully factored.We have expressed the original expression as a product of four linear factors, including the repeated factor. There are no further factors to extract, and the expression is fully factored.