Learn Class 8 Math - Exponents and Powers

A number multiplied by a power of the number gives a number's multiplicative power. The form of the formula is ab. The variables a and b indicate how many times we will need to multiply a to arrive at our result. The base is A, and the exponent is B.

For example, Consider 9³. Here, 9³ indicates that we need to multiply the base number 9 by three to obtain the answer, which is 27.

Powers with Negative Exponents

Any non-integer power with a negative exponent is essentially its reciprocal.

When there is an exponent -b on an integer a, a-b = 1ab.

Exponential form refers to the operation of multiplying the number by its exponents.

This is how it is written:

  • For example, 10 represents the base, 9 represents the exponent, and the complete number represents the power.
  • The number 10 raised to power 9 is pronounced as 10. Positive or negative exponents are both possible.

Hence, if we multiply 10 by nine we get: 10 * 10 * 10 * 10 * 10 * 10 * 10 * 10 * 10.

Exponents and Powers Sample Questions for Class 8

Question 1

By what number should (-36)^-1 be divided so that the quotient is (-9)^-1?
A. (-4)^-1
B. 1/4
C. (1/4)^-1
D. (-1/4)

Question 2

{ [ ( 12 × (1/3) × 5)^2]^0}^3 = ?
A. 1
B. 64000000
C. 0
D. 3200000

Question 3

What is standard form of 0.0053 × 10 ^-3?
A. 53 × 10^7
B. 0.053 × 10^-6
C. 53 ×10^-7
D. 0.00053 × 10 ^7

Question 4

If x = (3/2) ^ 3 × (2/3) ^ -2, find the value of x^-1
A. 32/243
B. 243/32
C. (3/2)^ 5
D. (3/2)^ -6

Question 5

Solve : {[ (1/3)²]⁰}² + [ ( -2/3)²]³
A. 665/729
B. 793/729
C. 17/729
D. 145/729