Rationalise the denominator of 25/sqrt(5)

In maths when we are asked to re express something we really only have 2 tricks. Multiply by 1, or add Zero. The hard part is finding how to express 1 or zero to suit the problem. For this one we should multiply by sqrt(5)/sqrt(5) = 1. We multiply the top and bottoms individually and unisng the definition of a square root we have 25/sqrt(5) * sqrt(5)/sqrt(5) = 25sqrt(5)/5 = 5sqrt(5)

SO

Related Maths A Level answers

All answers ▸

Differentiate the function y=4sqrt(x)


Let X be a normally distributed random variable with mean 20 and standard deviation 6. Find: a) P(X < 27); and b) the value of x such that P(X < x) = 0.3015.


Where do the graphs of y=3x-2 and y=x^2+4x-8 meet?


Find the volume of revolution when the area B is rotated 2 pi radians about the x axis