Reference Angles Find the reference angle and Find

Reference Angles Find the reference angle and Find Sin, Cos and Tan using reference angles.

Find the reference angle Most important idea is the triangle is always drawn to the x axis The reference angle is the Positive angle made in the triangle closest to the origin y ’ x ’

Find the reference angle for 288 Draw 288 angle Draw triangle back to x axis Find reference angle y x ’ ’ is what is left over from 360 – 288 = ’ = 72

Find the reference angle for 98 Draw 98 angle Draw triangle back to x axis Find reference angle ’ is what is left over from 180 – 98 = ’ = 82 y ’ x

Find the reference angle for -55 Draw -55 angle Draw triangle back to x axis Find reference angle y x ’ ’ is what is the same as measured from zero but the positive angle |-55| = ’ = 55

Find the reference angle for y Draw angle Draw triangle back to x axis Find reference angle ’ is what is left over from 2 x ’

Find the reference angle y Find the reference angle for Draw angle Draw triangle back to x axis Find reference angle ’ is the difference of and ’ x

Find the reference angle y Find the reference angle for Draw angle Draw triangle back to x axis Find reference angle ’ is the difference of and - x ’

Find the Trig ratios of 315 without a calculator y Find the reference angle for 315 ’ is what is left from 360 – 315 = ’ = 45 fourth quad Cos is positive, Sin and Tan are negative x ’

Find the Trig ratios of 210 without a calculator y Find the reference angle for 210 ’ is what is how much more than 180 210 – 180 = ’ = 30 x ’ Third quad Tan is positive, Sin and Cos are negative

Find the Trig ratios of calculator without a y Find the reference angle for ’ is what is how much more than x ’ Third quad Tan is positive, Sin and Cos are negative

Find the Trig ratios of calculator without a y Find the reference angle for ’ is what is how much less than x ’ second quad Sin is positive, Cos and Tan are negative

Rule for positive functions y All Students Take Calculus A = all functions pos in Q I S = Sine and csc pos in Q II T = Tan and cot pos in Q III C = Cos and sec pos in Q IV S A x T C

Now, start your homework! y Hw pg 499 problems (35 -85 odds) x