Form 2 Unit 1 Lesson 3 – First and Second laws of Indices
Objective
At the end of the lesson, students should be able to:
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Use the first and second index laws or laws of indices.
First law of indices:
When multiplying numbers in the index form, if the bases are the same, the powers are added.
Second law of indices:
When dividing numbers in index form, if the bases are the same, the powers are subtracted.
Example 1
Write the expanded form of the following then simplify:
a. 33× 34 b. 22 ×22×32
Solution
a. 33× 34
=3×3×3×3×3×3×3 the base is 3 and the power is 7
33 × 34= 37
b. 22 ×22×32
=2×2×2×2×3×3
the bases are two 2 and 3 . 2 is repeated 4 times and 3 repeated 2 times =24×32
22 ×22×32=24×32
Example 2
Simplify
Solution
Write the expanded form of the following then simplify
Example 3
Using the first and second laws of indices, simplify the following and compare answers to solution 1 and solution 2.
a. 33×34 b.22×22×32
c.27 /23
Solution
Lesson Content