Answer:
cos13°
Step-by-step explanation:
Using the cofunction identity
sinx° = cos(90 - x)°
sin77° = cos(90 - 77)° = cos13°
Is this algebra?, i can help you with thats the suject
Answer:
the correct answer is the second
140 if I observed the image correctly.
Use the identity
sec^2x = 1 + tan^2 x
- so sec x = sqrt(1 + tan^2 x) then:-
tan x + sqrt( 1 + tan^2 x) = 1
sqrt ( 1 + tan^2 x) = 1 - tan x
1 + tan^2 x = 1 + tan^2x - 2 tan x
0 = -2 tanx
tan x = 0
x = 0, π
π is an extraneous root because sec 180 = -1
So the answer is 0 degrees
