The Trig Chart :)

Soo Brob its Danielle on Sarahs once again..

Sooooooooooooooooooooooo this week we learned the trig chart. IT IS VERY IMPORTANT and we will need it for the rest of our mathematical lives. The trig chart teaches us trig functions.

Sin over cos gives you tan

Key point: reciprocal of sin is csc

Reciprocal of cos is sec

Reciprocal of cot is tan (cot= sin over cos)

Sin0= 0

Sin 30 degrees pi over 6= ½

Sin 45 degrees pi over 4= square root of 2 over 2

Sin 60 degrees pi over 3= square root of 3 over 2

Sin 90 degrees pi over 2= 1

cos0= 1

cos 30 degrees pi over 6= square root of 3 over 2

cos 45 degrees pi over 4= square root of 2 over 2

cos 60 degrees pi over 3= 1/2

cos 90 degrees pi over 2= 0

csc0= undefined

csc 30 degrees pi over 6= 2

csc 45 degrees pi over 4= square of 2

csc 60 degrees pi over 3= 2 square of 2 over 3

csc 90 degrees pi over 2= 1

sec0= 1

sec 30 degrees pi over 6= 2 square root of 3 over 3

sec 45 degrees pi over 4= square root of 2

sec 60 degrees pi over 3= 2

sec 90 degrees pi over 2= undefined

tan0= 0

tan 30 degrees pi over 6= square root of 3 over 3

tan 45 degrees pi over 4= 1

tan 60 degrees pi over 3= square root of 3

tan 90 degrees pi over 2= undefined

cot0= undefined

cot 30 degrees pi over 6= square root of 3

cot 45 degrees pi over 4= 1

co 60 degrees pi over 3= square root of 3 over 3

cot 90 degrees pi over 2= 0

Example 1: cos 45°

So you go look on your trig chart and the answer is square root of 2 over 2

Example 2: sin 210°

First you have to subtract by 360° because 210° isn’t on your trig chart, and you get 30° so you look on your trig chart and it the answer would be ½

Example 3: cos (-30)

You look on your trig chart and you get square root of 3 over 2

P.S Sarah hates the trig chart.

---Danielle