Chapter 6 Test Review 6-1 Roots and Radical Expressions Simplify 6-4 Rational Exponents Write each expression in simplest form. 2 3 20. 𝑦 5 ∙ 𝑦 8 4 21. (3𝑥 2. √121𝑦10 22. 3. 5 1. √𝑝12 𝑞4 1 12𝑥 3 1 4𝑦 2 √243𝑥 5 𝑦15 6-2 Multiplying and Dividing Radical Expressions Multiply and simplify. 2 1⁄ 2 )(4𝑥 ⁄3 ) 6-5 Solving Square Root and Other Radical Equations Solve. Check for extraneous solutions. 4. √−9𝑥 2 𝑦 4 ∙ 3√12𝑥𝑦 23. √𝑥 + 1 = 𝑥 − 1 5 24. 2√5𝑥 + 2 = 3 5. √12𝑥 2 𝑦 ∙ √3𝑥𝑦 4 25. √7𝑥 − 6 − √5𝑥 + 2 = 0 6. 4√2𝑥 ∙ 3√8𝑥 26. (2𝑥 − 4)2 = 10 − 𝑥 3 Divide and simplify. Rationalize the denominator, if needed. 3 √18𝑦 2 7. 3 √12𝑦 162𝑎 8. √ 6𝑎3 3𝑎 3 9. √4𝑏2 𝑐 6-3 Binomial Radical Expressions Simplify if possible. 10. 3√32 + 2√50 4 4 11. 3√32 − 2√162 3 12. 14 √𝑥𝑦 − 3 3√𝑥𝑦 13. (1 − √5)(2 − √5) 14. (√2 + √7)2 Rationalize the denominator and simplify the answer. 16. 6-6 Function Operations 𝑥 Let 𝑓(𝑥) = −3𝑥 + 2, 𝑔(𝑥) = 5, ℎ(𝑥) = −2𝑥 2 + 9, and 𝑗(𝑥) = 5 − 𝑥. Find each value or expression. 27. 28. 29. 30. 31. (𝑓 ∘ 𝑗)(3) 𝑓(𝑥) − ℎ(𝑥) (ℎ ∘ 𝑔)(−5) (𝑔 ∘ 𝑓)(𝑎) (ℎ ∙ 𝑗)(𝑥) 6-7 Inverse Relations and Functions Find the inverse of each function. Is the inverse a function? Describe the domain and range of the inverse. 32. 𝑦 = (𝑥 + 4)2 − 4 33. 𝑓(𝑥) = √3𝑥 Multiply 15. 1 2+√14 √7+√2 3 2+ √𝑥 3 √𝑥 Simplify 17. √28 + 4√63 − 2√7 18. 6√45𝑦 2 + 4√20𝑦 2 19. 6√40 − 2√90 − 3√160 1 5 34. 𝑓(𝑥) = − 𝑥 + 2 6-8 Graphing Radical Functions Graph each function using transformations. 3 35. 𝑦 = − √8𝑥 − 56 + 4 36. 𝑦 = √25𝑥 + 75 − 1 1 37. 𝑦 = 4 √𝑥 − 1 + 5 Word Problems 38. The formula s = 0.04n + 2500 gives an employee’s monthly salary s, in dollars, after selling n dollars in merchandise at an appliance store. a. Find the inverse of the function. Is the inverse a function? b. Use the inverse to find the amount of merchandise sold if the employee’s salary was $2820 last month. 39. The volume of a sphere of radius r is 4 V r3 3 a. Use the formula to find r in terms of V. Rationalize the denominator. b. Use your answer to part (a) to find the radius of a sphere with volume 100 cubic inches. Round to the nearest hundredth. 40. What are the lengths of the sides of the trapezoid shown at the right if the perimeter of the trapezoid is 17 cm?