Question

8) ∆ABC
m( ^A)= 90°
sim^ABC =1\2
_____________
Cos^ABC=?​

Answer 1

$m(\angle A)=90^o \\ \sin(\angle ABC)=\frac{1}{2} \\ \Rightarrow \angle B=30^o \\ \Rightarrow \angle C=60^o \\ \Rightarrow\boxed{ \cos(\angle ABC )=\frac{\sqrt3}{2}}$