What is (1+cosx)/(1+secx) for x=pi/3?

1 Answer
Jan 2, 2017

(1+cosx)/(1+secx)=cosx and for x=pi/3, it is 1/2.

Explanation:

(1+cosx)/(1+secx)

= (1+cosx)/(1+1/cosx)

= (1+cosx)/((cosx+1)/cosx)

= (1+cosx)xxcosx/(1+cosx)

= cosx

Hence (1+cosx)/(1+secx)=cosx for all values of x

and for x=pi/3

(1+cosx)/(1+secx)=(1+cos(pi/3))/(1+sec(pi/3))

= (1+1/2)/(1+2)=(3/2)/3=3/2xx1/3=1/2

As cosx=cos(pi/3)=1/2

for x=pi/3, (1+cosx)/(1+secx)=cosx