I'll just do the first one:
tan(t) + = sec(t)
Rationalize the denominator of the second term by
multiplying it by
tan(t) +
tan(t) +
tan(t) +
You know the identity . When it
is solved like this the right side
is the same form as the denominator and so we can write
as
tan(t) +
And we cancel the cos(t) on top into the cosē(t) in the bottom
tan(t) +
tan(t) +
Now we substitute for :
Combine the fractions (they already have a common denominator):
Edwin