Daily Practice - Higher Plus

The point (20, 21) lies on the circle x² + y² = 841. Work out the gradient of the tangent to the circle at that point.The point (20, 21) lies on the circle x^2 + y^2 = 841. Work out the gradient of the tangent to the circle at that point.

A bag holds 7 red, 7 blue and 4 green counters. Two are taken without replacement. Given neither is green, what is the probability both are red?

On a histogram, a 4-wide bar and a 16-wide bar have the same frequency density of 2.5. How many more values are in the wider class?

Rationalise the denominator of 6/3, giving your answer in its simplest form.Rationalise the denominator of 6/sqrt(3), giving your answer in its simplest form.

Solve x² + 5x + 6 > 0.Solve x^2 + 5x + 6 > 0.