New SAT Math Workbook

4 b the question asks you to recognize the set of

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: her, the result is always an integer.) Choice (A), which incorporates the concept of absolute value, cannot be the correct answer, since the absolute value of any integer is by definition a positive integer. (E) Either x – 3 > 4 or x – 3 < –4. Solve for x in both inequalities: x > 7; x < –1. (B) If x = 0, y = –1. The point (0,–1) on the graph shows this functional pair. For all negative values of x, y is the absolute value of x, minus 1 (the graph is translated down one unit). The portion of the graph to the left of the y-axis could show these values. For all positive values of x, y = x, minus 1 (the graph is translated down one unit). The portion of the graph to the right of the y-axis could show these values. (D) Substitute 2 for x in the function: f 1 2. 3. 4. (D) The expression given in the question is equivalent to 4 · 4n. In this expression, base numbers are the same. Since the terms are multiplied together, you can combine exponents by adding them together: 4 · 4n = 4(n+1). (A) Raise both the coefficient –2 and variable x2 to the power of 4. When raising an exponent to a power, multiply together the exponents: (–2x2)4 = (–2)4x(2)(4) = 16x8 3. 4. (C) Any term to a negative power is the same as “one over” the term, but raised to the positive power. Also, a negative number raised to a power is negative if the exponent is odd, yet positive if the exponent is even: –1(–3) + [–1(–2)] + [–12] + [–13] = − + + 1 – 1 11 =0 11 5. ( )= 1 −3 − 1 2 1 2 1 2 1 5. = 2−3 − 2 = −1 − 2 1 The correct answer is 16. Express fractional exponents as roots, calculate the value of each term, and then add: 4 3 2 + 4 3 2 = 4 3 + 4 3 = 64 + 64 = 8 + 8 = 16 = 1− 2 1 = 1 2 www.petersons.com 268 Chapter 15 Exercise 5 1. (A) One way to approach this problem is to substitute each answer choice for x in the function, then find f(x). Only choice (A) provides a value for which f(x) = x: f Exercise 6 1. (B) To determine the function’s range, apply the rul...
View Full Document

Ask a homework question - tutors are online