Use “The Chart” to remember these values.

Example 1 The question this problem is asking is “What is the angle measure of the right triangle that has the side opposite angle x as and the hypotenuse is 2.” The question this problem is asking is “What is the angle measure of the right triangle that has the side adjacent angle x as and the hypotenuse is 2.” To get x alone, multiply by the inverse of sine:To get x alone, multiply by the inverse of cos: arc sin This is only the possibility for the 1 st quadrant. According to the table, 120° is also a possibility, along with any coterminal angles. arc cos This is only the possibility for the 2 nd quadrant. According to the table, 225° is also a possibility, along with any coterminal angles. These terms are interchangeable (calculator or chart)

Example 2 What happens when something is multiplied by its inverse? It helps to set the expression equal to x They cancel each other out.

Each trig function must always be followed by an angle, So... Multiply both sides by sin Draw a picture w/ this info: Cosine uses the adjacent side, so calculate it: r = 3, y = 2

Example 3 f = 17 (adj) d = 32 (hyp) Which trig function?

Example 4 Angle of Depression has to be formed by a horizontal line. 20 ft 100 ft Be careful not to calculate this angle!

Example 5 To solve a triangle means to find all the missing pieces; 3 angles & 3 sides 33° 5.8

23 45 (opp) (hyp)

HW: Page 309