Question

Please answer these in 5 min for extra points
Q13,14,15

Answer 1

(1+sinx +cosx )/(1- sinx +cosx )

taking common cosx

= cosx(secx + tanx + 1)/cosx (secx - tanx + 1)

we know that

(sec^2x - tan^2x)=1

Now

= (secx + tanx) + (sec^2x - tan^x)/(secx - tanx + 1)

= (secx + tanx)(secx - tanx + 1)/(secx - tanx + 1)

= secx + tanx

hence LHS = RHS

proved

14)(cotx + cosecx - 1)/(cotx - cosecx + 1)

we know that

cot^2x + cosec^2x=1

(cotx + cosecx)- (cot^2x - cosec^2x )/(cotx - cosecx + 1)

(cotx + cosecx )(cotx - cosecx + 1)/(cotx - cosecx + 1)

cotx - cosecx

solution 15 is attached above

Answer 2

Answer:

Solution is in the attachment