If in any ∆ABC, C = 105o, B = 45o, a = 2, then find b.


We know in a triangle,


A + B + C = 180°


A = 180° - B - C


Substituting the given values, we get


A = 180° - 45° - 105°


A = 30°


Let a, b, c be the sides of the given triangle. Then by applying the sine rule, we get




Now substituting the corresponding values we get



Substitute the equivalent values of the sine, we get





Hence the value of b is 2√2 units.


2