Which of the following equations are identities. check all that apply a) cotx= cosx/sinx b) cscx=1/cosx c) tanx=1/cotx d) cscx=1/secx

A) cotx = cosx/sinx    

C) tanx = 1/cotx

Step-by-step explanation:

A)

cosx/sinx = 1/(sinx/cosx) = 1/tanx = cotx

Therefore, cotx = cosx/sinx  

C)

Similarly;

1/tanx = cotx

Therefore,

1 = tanxcotx

1/cotx = tanx

and

tanx = 1/cotx

B) cscx=1/cosx is not true since;

1/cosx = secx

and

cscx = 1/sinx

∠acb = 8°

step-by-step explanation:

∠xba lies on the circle and is half the measure of the intercepted arc ax

hence

measure of arc ax = 2 × 42° = 84°

∠acb is outside the circle and is

∠acb = (arcab - arcax ), hence

∠acb = 0.5 (100 - 84) = 0.5 × 16° = 8°