Indices and surds
Lesson 11 of 14
Simplifying surds
Objective. Simplify surds and rationalise a simple denominator.
The key idea
Split the number under the root into a square factor and the rest: √50 = √25 × √2 = 5√2. To rationalise, multiply top and bottom by the surd.
Worked example
Simplify 6/√3.
- 1Multiply top and bottom by √3: 6√3 / 3.
- 26 ÷ 3 = 2.
Answer: 2√3
Practice
Each question comes with a picture and a listen button. Try it first, then reveal the answer.
Common mistake. Writing √(a + b) as √a + √b.
Your progress
Tick each step as you finish it — Continue brings you back here.
0 of 5 steps complete