Introduction Trigonometric identities often confuse Class 10 students, but they are actually the simplest once you know the logic. These identities are the backbone of trigonometry and are repeatedly used in exams. In this blog, I’ll walk you through the proof of three trigonometric identities with clear steps and examples. You’ll also find a video lesson embedded for easier understanding.…
Category: Class 10 Ncert Concepts & Questions
Example 7: In a ΔPQR, right-angled at Q (see Fig. 8.20), PQ = 3 cm and PR = 6 cm. Determine ∠QPR and ∠PRQ.
Given: PQ = 3 cm, PR = 6 cm, ∠Q = 90° To find: ∠QPR = ? and ∠PRQ = ? Solution: In right ΔPQR, Let ∠PRQ = θ Also, (p / h) = sin θ PQ / PR = sin θ 3 / 6 = sin θ 1/2 = sin θ We know, sin 30° = 1/2 So, θ…
Example 2: If ∠B and ∠Q are acute angles such that sin B = sin Q, then prove that ∠B = ∠Q
To Prove: ∠B=∠Q\angle B = \angle Q Given: ∠B and ∠Q are acute angles sin B = sin Q Proof: Let us consider two right triangles: ΔABC, right-angled at C ΔPQR, right-angled at R Step 1: Write sine values in each triangle In ΔABC: sinB=ACAB⋯(1)\sin B = \frac{AC}{AB} \quad \cdots (1) In ΔPQR: sinQ=PRPQ⋯(2)\sin Q = \frac{PR}{PQ} \quad \cdots…
Example 1 : If tan A = 4/3, find other Trigonometric Ratios of angle A
This is a typical Class 10 CBSE trigonometry problem. If you’re given tan A = 4/3, the goal is to find the remaining five trigonometric ratios. Let’s solve this step by step using the triangle sides: perpendicular, base, and hypotenuse. Step-by-Step Solution: We are given: tan A = 4/3 That means: Perpendicular = 4 units Base = 3 units Now,…