Question

Question. 1 :

In ∆ ABC, right-angled at B, AB = 24 cm, BC = 7 cm. Question
2.
If Sin A = 3/4, Calculate cos A and tan A.​

Answer 1

Answer to Question 1:

AB= 24cm

BC = 7cm

<B = 90°

AC = ?

Using Pythagoras theorem :-

AC^2 = AB^2 + BC ^ 2

AC^2 = 24^2 + 7^2

AC^2 = 576 + 49

AC^2 = √625

AC = 25

Answer to Question 2 :-

sin A = 3/4

CosA = ?

TanA = ?

SinA = Opp. side/Hypotenuse

= 3/4

(Construct a triangle right angled at B with one side BC of 3cm and hypotenuse AC of 4cm.)

Using Pythagoras theorem :-

AC^2 = AB^2 + BC ^ 2

4² = AB² + 3²

16 = AB + 9

AB = √7cm

CosA = Adjacent side/Hypotenuse

= AB/AC

= √7/4

TanA= Opp. side/Adjacent side

=BC/AB

= 3/√7