Higher Plus

On a histogram, a 5-wide bar and a 15-wide bar have the same frequency density of 2. How many more values are in the wider class?

Simplify 72 + 2, giving your answer in the form a b.Simplify sqrt(72) + sqrt(2), giving your answer in the form a sqrt(b).

Use the iteration x(n+1) = cube root of (6x(n) + 4) with x(0) = 1. Work out x(1) to 3 decimal places.

A cyclist speeds up steadily from 7 m/s to 14 m/s over 8 seconds. Use the area under the velocity-time graph to find the distance travelled.

The point (9, 12) lies on the circle x² + y² = 225. Work out the gradient of the tangent to the circle at that point.The point (9, 12) lies on the circle x^2 + y^2 = 225. Work out the gradient of the tangent to the circle at that point.