Question

In a Δ ABC right angled at B, if AB=4,BC=3 Find Sin A,Cos A,Tan A Δ

Answer 1

We have, AB = 4 and BC = 3.
By Pythagoras theorem, we have
$A{C}^2=A{B}^2+B{C}^2$
$\Rightarrow AC=\sqrt{A{B}^2+B{C}^2}$
$\Rightarrow AC=\sqrt{4^2+3^2}=\sqrt{25}=5$
When we consider the t-ratios of $\angle A$, we have
Base = AB = 4, Perpendicular = BC = 3, Hypotenuse = AC = 5.
$\therefore sinA=\frac{BC}{AC}=\frac{3}{5},cosA=\frac{AB}{AC}=\frac{4}{5},tanA=\frac{BC}{AB}=\frac{3}{4}$