CBSE Class 10 Mathematics Standard 2023: question 23(a)

Hints

Open one hint at a time and try again before the next.

Step-by-step solution

Each step shows the marks it earns, as an examiner would award them. Checked by an independent re-solve from the question paper.

1. Square both sides of $\sin \theta +\cos \theta =\sqrt{3}$: ${\sin }^2\theta +{\cos }^2\theta +2\sin \theta \cos \theta =3$.

   1 mark

2. Use ${\sin }^2\theta +{\cos }^2\theta =1$: $1+2\sin \theta \cos \theta =3$.

   ½ mark

3. $2\sin \theta \cos \theta =2\Rightarrow \sin \theta \cos \theta =1$.

   ½ mark

Answer: sin θ · cos θ = 1

Revise the chapter

• Chapter: Introduction to Trigonometry (notes, formulas, where marks are lost and every past question)
• Topic: Proving Simple Trigonometric Identities