Q. 4 A3.9( 36 Votes )

# In ∆ABC, right angled at B, AB = 24 cm, BC = 7 cm. Determinea. sin A, cos Ab. sin C, cos C (i)

(a) sin A

We know that, So, here θ = A

Side opposite to A = BC = 7

Hypotenuse = AC = ?

Firstly we have to find the value of AC.

So, we can find the value of AC with the help of Pythagoras theorem.

According to Pythagoras theorem,

(Hypotenuse)2 = (Base)2 + (Perpendicular)2

(AB)2 + (BC)2 = (AC)2

(24)2 + (7)2 = (AC)2

576 + 49 = (AC)2

(AC)2 = 625

AC =625

AC =±25

But side AC can’t be negative. So, AC = 25cm

Now, BC = 7 and AC = 25

So, Cos A

We know that, So, here θ = A

Side adjacent to A = AB = 24

Hypotenuse = AC = 25

So, (b) sin C

We know that, So, here θ = C

The side opposite to C = AB = 24

Hypotenuse = AC = 25

So, Cos C

We know that, So, here θ = C

Side adjacent to C = BC = 7

Hypotenuse = AC = 25

So, Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Related Videos  Champ Quiz | Trigonometric Identities33 mins  Trigonometric Identities33 mins  NCERT | Trigonometric Identities52 mins  Quiz | Task on Trigonometric Ratios46 mins  Algebraic Identities48 mins  Quiz on Trigonometric Ratios31 mins  Quiz | Practice Important Questions on Trigonometrical Identities46 mins  T- Ratios of Specified Angles58 mins  Trick to learn all Trigonometric Formulae28 mins  Testing the T- Ratios of Specified Angles57 mins
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation view all courses 