Vectors and trigonometric ratios

Question 1 of 10

From a point 50 m from the foot of a tower on level ground, the angle of elevation of the top is 45°. How tall is the tower?

Question 2 of 10

The vectors (2, k) and (6, 9) are parallel. Find k.

Question 3 of 10

What is the exact value of tan 60°?

Question 4 of 10

If tan θ = 8/15 and θ is acute, find sin θ + cos θ.

Question 5 of 10

A vector starts at (1, 2) and ends at (4, 6). How long is it?

Question 6 of 10

In a right-angled triangle, sin θ = 5/13. Find cos θ.

Question 7 of 10

What is the exact value of sin 30°?

Question 8 of 10

The magnitude of the vector (5, 12) is

Question 9 of 10

In a right triangle, the side opposite 30° is 4 cm. The hypotenuse is

Question 10 of 10

If a = (3, −2) and b = (−1, 5), find 2a − b.