Powers:Β 

When we want to multiply a number by itself, we use powers. As an example, 5 x 5 x 5 x 5 is usually written as 5^4. The number 4 shows the number of 5 to be multiplied. The power is 4. The number 5 is called the base. Β 

Square roots:Β When 5 is squared we getΒ 25. That is 5^2= 25. The reverse of this process is called finding a square root. The square root of 25 is 5. This is written as√ 25 = 5. also that when βˆ’5 is squared we again get 25, that is (βˆ’5)^2 = 25. This means that 25 has another square root, βˆ’5. In general, a square root of a number is a number which when squared gives the original number. There are always two square roots of any positive number, one positive and one negative. Well negative numbers do not have any square roots. Most calculators have a square root button, square root mark. Check that you can use your calculator correctly by verifying that √ 79 = 8.8882, to four decimal places. Your calculator will only give the positive square root, but you should be aware that the second, negative square root is βˆ’8.8882. The square root of the combination of two integers is equal to the product of the square roots of the two numbers, which is an important result. Β 

For example, √ 16 Γ— 25 = √ 16 Γ— √ 25 = 4 Γ— 5 = 20 More, √ ab = √ a Γ— √ bΒ