Trigonometry

Math 20-1: angles in standard position and the unit circle.

13 questions, free, marked as you go with a worked explanation on every one.

What this covers

What is sin(90°)?
What is cos(0°)?
An angle in standard position is measured starting from the positive:
What is sin(180°)?
What is cos(90°)?
What is sin(270°)?
In which quadrant is an angle of 150°?
Which statement about the unit circle is NOT true?
An observer stands 40 m from the base of a building. The angle of elevation from her eyes to the top of the building is 52 degrees, and her eyes are 1.6 m above the ground. How tall is the building, in metres, rounded to one decimal place?
A ladder leans against a wall, making an angle of 65 degrees with the ground. The ladder is 4 m long. How high up the wall does it reach, in metres, rounded to one decimal place?
From the top of a 60 m cliff, the angle of depression to a boat is 18 degrees. How far is the boat from the base of the cliff, in metres, rounded to one decimal place?
In a right triangle, which ratio is defined as the side opposite the angle divided by the hypotenuse?
A right triangle has a hypotenuse of 13 cm and one leg of 5 cm. What is the measure of the angle opposite the 5 cm leg, in degrees, rounded to one decimal place?