The problem
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the answer I have for this problem is
a) sec x
b) 1+tan x.
c ) csc x
d0 tan x
Answer provided by our tutors
cos(x) + cos(x)(tan^2(x))
Since tan(x) = sin(x)/cos(x) we have:
cos(x) + cos(x)(tan^2(x)) =
= cos(x) + cos(x)(sin(x)/cos(x))^2 =
= cos(x) + cos(x)(sin^2(x)/cos^2(x)) =
= cos(x) + sin^2(x)/cos(x)) =
= (cos^2(x) + sin^2(x))/cos(x) =
= 1/cos(x)
We are also using the fact that cos^2(x) + sin^2(x)=1.
1/cos(x) = sec(x)
The answer is a) sec x.