# StudySquare

# Cosine for OCR A-level Maths

This page covers the following topics:

1. Cosine

2. Cosine graphs and transformations

Cosine of an angle is a ratio between the side adjacent to the angle and the hypotenuse of a triangle.

The diagram shows a cosine graph.

# 1

Find a if cosB = 0.9 and c = 40.

36

# 2

Find a if cosB = 0.3 and c = 20 cm.

6 cm

# 3

Write down the coordinates of point B on the cosine graph.

(270º, 0)

# 4

Find b if cosA = 0.5 and c = 10.8.

5.4

# 5

Provide the point at which a cosine graph crosses the y axis.

(0º, 1)

End of page