MATH 1050 SECTION 2 QUIZ 1 FALL 2009 1. Simplify p 75x2 y −4 so that all exponents are positive. solution. √ √ √ √ 75 x2 3 25|x| 5 3|x| p = . = = y2 y2 y4 Note that we could have put |y 2 | in the denominator. This is not strictly necessary since y 2 is already positive. We do need absolute value brackets around x since x could be positive or negative. s p 75x2 y −4 75x2 = y4 √ 2. Completely factor and simplify: 3(3 − 4x)2 − 8(3 − 4x)(5x − 1). solution. 3(3 − 4x)2 − 8(3 − 4x)(5x − 1) = 3(3 − 4x)(3 − 4x) − 8(3 − 4x)(5x − 1) = (3 − 4x)(3(3 − 4x) − 8(5x − 1)) = (3 − 4x)(9 − 12x − 40x + 8) = (3 − 4x)(17 − 52x). 3. Factor 3x2 − 5x + 2. solution. There are several ways to factor this polynomial. Any method is acceptable so long as you get the right answer. We’ll factor by grouping: 3x2 − 5x + 2 = 3x2 − 3x − 2x + 2 = 3x(x − 1) − 2(x − 1) = (x − 1)(3x − 2). Remember that it is always good to check your answer by multiplying out the factorization and verifying that you get back the original polynomial. 4. Complete the subtraction and simplify: 3 − 5. x−1 solution. 3 3 5(x − 1) 3 − 5x + 5 8 − 5x −5= − = = . x−1 x−1 x−1 x−1 x−1 1