Exponents and powers nikita class 8
Download as PPTX, PDF6 likes9,978 views
The document discusses exponents and powers. It explains that the exponent tells you how many times to use the base number in a multiplication. Positive, zero, and negative exponents follow a simple pattern. Some key laws of exponents include a0 = 1, and am × an = am+n. Examples are provided to illustrate exponent rules and evaluating expressions with exponents.
Exponents and powers nikita class 8
- 2. The exponent of a number says how many times to use that number in a multiplication. It is written as a small number to the right and above the base number. In this example: 82 = 8 × 8 = 64 (The exponent "2" says to use the 8 two times in a multiplication.) Exponents are also called Powers or Indices
- 3. What if the Exponent is 1, or 0?
- 4. 1 If the exponent is 1, then you just have the number itself (example 91 = 9) 0 If the exponent is 0, then you get 1 (example 90 = 1) Example: Powers of 5 52 1 × 5 × 5 25 51 1 × 5 5 50 1 1 5-1 1 ÷ 5 0.2 5-2 1 ÷ 5 ÷ 5 0.04 If you look at that table, you will see that positive, zero or negative exponents are really part of the same (fairly simple) pattern
- 5. LAWS OF EXPONENTS WITH EXAMPLES 32 × 33 = 32 + 3 = 35 = 243 36/32 = 36 – 2 = 34 = 81 If a is any number except 0, then a0 = 1. 93/93 = 93 – 3 = 90 = 1 (22)3 = (2)2 × 3 = 2 6 = 64 (10)5 = (2 × 5)5 = 25 × 55
- 7. Use of exponents to express small no. in standard form
- 8. ANSWER THE FOLLOWING QUESTIONS : Q 1. The value of 25 is _________ . (a) 3 (b) 10 (c) 32 (d) 7 ans. c In standard form 21600000 is written as • 2.16 × 107 (b) 216 × 107 (c) 2.16 × 105 (d) 216 × 100000 ans.a . Charge of an electron is 0.000,000,000,000,000,000,16 coulomb and in exponential form it can be written as • 16 × 10-18 coulomb (b) 1.6 × 10-21 coulomb (c) 1.6 × 10-19 coulomb (d) 16 × 10-21 coulomb ans.c