In the verge of coronavirus pandemic, we are providing FREE access to our entire Online Curriculum to ensure Learning Doesn't STOP!

# Ex.12.1 Q5 Exponents and Powers Solution - NCERT Maths Class 8

Go back to  'Ex.12.1'

## Question

Find the value of m for which \begin{align}({5^m} \div {5^{ - 3}}) = {5^5}\end{align}

Video Solution
Exponents And Powers
Ex 12.1 | Question 5

## Text Solution

What is known?

Expression in exponential form

What is unknown?

Value of $$m$$

Reasoning:

${a^m} \div {a^n} = {a^{m - n}}$

Steps:

\begin{align}({5^m} \div {5^{ - 3}})&= {5^5}\\{5^{m - ( - 3)}} &= {5^5}\\{5^{m + 3}} &= {5^5}\end{align}

On both the side powers have the same base, so their exponents must be equal.

$$\therefore + 3 = 5 \to m = 5 - 3 \to m = 2$$

Learn from the best math teachers and top your exams

• Live one on one classroom and doubt clearing
• Practice worksheets in and after class for conceptual clarity
• Personalized curriculum to keep up with school