tangene it Positive in the first quadrant, and the third quadrant.
so PI/6 and PI/6+PI or 7PI/6
degrees? 30 and 210
What are the two radians and degrees for the following?
1. tanè=sqrt 3 over 3
Answer: pi/6 or 30deg
What is the other radian and degree?
2. cotè=-1
3. secè=2
4. cscè= sqrt 2
2 answers
for each one, use the CAST rule to find where else a certain trig ratio is positive or negative
for #1, you have found the angles in quadrant I, but the tangent is also positive in III, (the T of CAST)
So è = 30 degrees in I ---> pi/6
or è = 210 in III ------ 7pi/6
#2
cotè=-1
then tanè=-1 , tan is negative in II or IV
è = 180-45 = 135 ----> 3pi/4
e = 360-45 = 315 ----> 7pi/4
#3
secè = 2
cosè = 1/2 , è will be in I or IV
take over
for #1, you have found the angles in quadrant I, but the tangent is also positive in III, (the T of CAST)
So è = 30 degrees in I ---> pi/6
or è = 210 in III ------ 7pi/6
#2
cotè=-1
then tanè=-1 , tan is negative in II or IV
è = 180-45 = 135 ----> 3pi/4
e = 360-45 = 315 ----> 7pi/4
#3
secè = 2
cosè = 1/2 , è will be in I or IV
take over
1 answer