cotx = 6/5 ---> tanx = 5/6
secy = 3/2 ---> cosy = 2/3
sketch your triangles in quad I
using Pythagoras,
if tanx = 5/6
r^2 = 25 + 36 = 61
r = β61
if cosy = 2/3
by Pythagoras: 2^2 + Y^2 = 3^2
Y = β5
tany = β5/3
tan(x+y) = (tanx + tany)/(1 - tanxtany)
= (5/6 + β5/3)/(1 - (5/6)(β5/3)
= ( (5 + 2β5)/6 )/ ( (6 - 5β5)/6)
= (5 + 2β5)/(6 - 5β5)
Given that 0 β€ π₯ β€ π/2and 0 β€ π¦ β€π/2
find the exact value of π‘ππ(π₯ + π¦) if πππ‘(π₯) =6/5 and π ππ(π¦) =3/2
1 answer