Exponents And Powers Class 8

Exponents and Powers class 8 – For any non-zero integer p, \(p^{-k}=\frac{1}{p^{k}}\), where m is a positive integer. Also, \(p^{k}\times p^{m}=p^{k+m}\). Lets evaluate the value of \(2^{-2}\;\;and\;\;\frac{1}{4^{-3}}\). Here, \(2^{-2}=\frac{1}{2^{2}}=\frac{1}{4}=0.25\). Similarly, \(\frac{1}{4^{-3}}= 4^{3}=64\)

Example 1: Express 79,00,000,000 in standard form.

Solution: 79,00,000,00 = \(7.9\times 10^{8}\)

Numbers with negative exponents obey the following laws of exponents.

  1. \(\frac{a^{m}}{b^{m}}=\left ( \frac{a}{b} \right )^{m}\)
  2. \(a^{0}=1\)
  3. \(a^{m}\times b^{m}=\left ( ab \right )^{m}\)
  4. \(\left ( a^{m} \right )^{n}=a^{mn}\)

Solve: \(\left ( \frac{5}{8} \right )^{-7}\times \left ( \frac{8}{5} \right )^{-5}\)

\(\left ( \frac{8}{5} \right )^{7}\times \left ( \frac{5}{8} \right )^{5}=\frac{8^{2}}{5^{5}}=\frac{64}{25}\)

Exponents and Powers class 8 Examples

Exponents And Powers Class 8
Exponents And Powers Class 8
Exponents And Powers Class 8
Exponents And Powers Class 8
Exponents And Powers Class 8
Exponents And Powers Class 8


Practise This Question

What must be subtracted from x33x2+5x1 to get 2x3+x24x+2 ?