In: Math
Which expression is equivalent to secαcos(2α) for all values of α for which secαcos(2α) is defined?
Select the correct answer below:
21−tan2α
2cos2α
2sin2α
2cosα−secα
1−tan2α
sec
cos ( 2
)
cos ( 2
) = 2 cos^2
- 1
sec
= 1 / cos
so we get
1 / cos
( 2 cos^2
- 1)
1/ cos
* 2 cos^2
- 1/ cos
2 cos
- 1/ cos
2 cos
- sec
2 cos ![]() ![]() |