ASVAB Mathematics Knowledge Practice: Cube and Square Roots - dummies

ASVAB Mathematics Knowledge Practice: Cube and Square Roots

By Consumer Dummies

Some questions on the Mathematics Knowledge subtest on the ASVAB are guaranteed to be totally radical. Not in the ’80s sense, but because they deal with numbers that are square and cube roots of other numbers.

Practice questions

  1. Solve

    ASVAB_0601

    when x = –3.

    A. 152
    B. 25
    C. 1.5
    D. 15

  2. Given

    ASVAB_0602

    simplify the expression.

    ASVAB_0603

Answers and explanations

  1. The correct answer is Choice (D).

    First evaluate the expression inside the square root symbol by filling in the value of x:

    ASVAB_0604

    Find

    ASVAB_0605

    by determining that

    ASVAB_0606

  2. The correct answer is Choice (C).

    Both radicals are cube roots, so multiply the radicands. Because

    ASVAB_0607

    you get

    ASVAB_0608

    Factor and simplify, and look for perfect cubes to make it easier:

    ASVAB_0609

    Rewrite the numbers and variables as the product of radicals so you continue to work with like terms:

    ASVAB_0610

    Solve what you can and simplify:

    ASVAB_0611