Surds and Indices


  1. Evaluate ( 0.00032)2/5











  1. View Hint View Answer Discuss in Forum

    Given that
    (0.00032)2/5 = (32/100000)2/5
    Solve the equation by algebra Law

    Correct Option: D

    Given that
    (0.00032)2/5 = (32/100000)2/5
    Solve the equation by algebra Law
    = (25/105)2/5
    = {(2/10)5}2/5
    = (2/10)5x2/5
    = (1/5)2 = 1/25


  1. If {(24)1/2}? = 256, find the value of '?'.











  1. View Hint View Answer Discuss in Forum

    Given that, (24x 1/2)? = 256
    Apply the law of Fractional Exponents and Laws of Exponents
    (am)n = am x n ----------------1
    (am) x (an) = am + n-------------------2
    am ÷ an = am ? n----------------3
    and if pX = pY then X will be equal to Y. means X = Y;----------------4

    Correct Option: C

    Given that, (24x 1/2)? = 256
    Apply the law of Fractional Exponents and Laws of Exponents
    ⇒ (22)? = 28
    ⇒ 22 x ? = 28
    ⇒ 2 x ? = 8
    ∴ ? = 8/2 = 4



  1. If 10 + ∛ x = 4, then what is the value of x ?









  1. View Hint View Answer Discuss in Forum

    Given, √10 + ∛ x = 4
    On squaring both sides,
    After squaring the both sides,
    Now, cubic on both sides,
    Then solve the equation.

    Correct Option: B

    Given, √10 + ∛ x = 4
    On squaring both sides, we get
    10 + ∛x = 16
    ⇒ ∛x = 6
    Now, cubic on both sides, we get
    x = (6)3 = 216


  1. Value of ? in expression
    78.9 ÷ (343)1.7 x (49)4.8 = 7? is











  1. View Hint View Answer Discuss in Forum

    78.9 ÷ (343)1.7 x (49)4.8 = 7?
    Apply the law of Fractional Exponents and Laws of Exponents
    (am)(an) = am+n
    am÷an=am?n
    am/an=am?n
    (am)n = amn

    Correct Option: A

    78.9 ÷ (343)1.7 x (49)4.8 = 7?
    Apply the law of Fractional Exponents and Laws of Exponents
    (am)(an) = am+n
    am÷an=am?n
    am/an=am?n
    (am)n = amn
    78.9 ÷ (343)1.7 x (49)4.8 = 7?
    ⇒ 78.9 ÷ (73)1.7 x (72)4.8 = 7?
    ⇒ 78.9 ÷ 75.1 x 79.6 = 7?
    ⇒ 78.9 - 5.1 + 9.6 = 7?
    ⇒ 718.5 - 5.1 = 7?
    ∴ ? = 13.4



  1. If a2x + 2 = 1,where a is a positive real number other than 1, then x = ?









  1. View Hint View Answer Discuss in Forum

    Given that, a2x + 2 = 1
    Apply the algebra Law,
    p0 = 1
    and if
    pX = pY
    then X will be equal to Y. means X = Y;

    Correct Option: B

    Given that, a2x + 2 = 1
    Apply the algebra Law,
    p0 = 1

    ⇒ a2x + 2 = a0
    Apply the algebra law
    pX = pY then X will be equal to Y. means X = Y;

    ⇒ 2x + 2 = 0
    ⇒ x = -2/2 = -1