Higher Plus

The point (5, 12) lies on the circle x² + y² = 169. Work out the gradient of the tangent to the circle at that point.The point (5, 12) lies on the circle x^2 + y^2 = 169. Work out the gradient of the tangent to the circle at that point.

A bag holds 6 red, 5 blue and 5 green counters. Two are taken without replacement. Given neither is green, what is the probability both are red?

On a histogram, a 10-wide bar and a 40-wide bar have the same frequency density of 2.5. How many more values are in the wider class?

Simplify 72 + 50, giving your answer in the form a b.Simplify sqrt(72) + sqrt(50), giving your answer in the form a sqrt(b).

The curve y = cos x° is drawn for 0 ≤ x ≤ 360. Write down the value of y when x = 90.The curve y = cos x° is drawn for 0 <= x <= 360. Write down the value of y when x = 90.