Question #835cb

1 Answer
Feb 12, 2017

Given

tana/tanb=sqrt3tanatanb=3

=>cotb/cota=sqrt3cotbcota=3

=>cotb=sqrt3cota......[1]

Again

sina/sinb=sqrt2

=>cscb/csca=sqrt2

=>csc^2b/csc^2a=2

=>(1+cot^2b)/(1+cot^2a)=2

Putting cotb=sqrt3cota

=>(1+3cot^2a)/(1+cot^2a)=2

=>1+3cot^2a=2+2cot^2a

=>3cot^2a-2cot^2a=2-1=1

=>cota=1=cot(pi/4)=cot(pi+pi/4)

=>a=pi/4 and (5pi)/4

Inserting a =pi/4 or (5pi)/4 in [1]

=>cotb=sqrt3cota

=>cotb=sqrt3xx1=cot(pi/6)=cot(pi+pi/6)

=>b=pi/6 and (7pi)/6