Chapter 8: Introduction to Trigonometry — Online MCQ Test
MATHS · Grade 10 · CBSE(NCERT)
Practice Chapter 8: Introduction to Trigonometry with a free chapter-wise online MCQ test.
This chapter covers: Trigonometric ratios Sine Cosine Tangent Cosecant Secant Cotangent Standard angles Trigonometric identities Complementary angles.
AI-generated questions from basic to board-exam level, with instant results and explanations.
Chapter 8: Introduction to Trigonometry — Important Questions & Answers
In a right-angled triangle, sin A is equal to:
- A. Opposite side/Hypotenuse
- B. Adjacent side/Hypotenuse
- C. Opposite side/Adjacent side
- D. Hypotenuse/Opposite side
Answer: A. Opposite side/Hypotenuse
By definition, sin A = perpendicular or opposite side divided by hypotenuse.
By definition, sin A = perpendicular or opposite side divided by hypotenuse.
The value of tan A in terms of sin A and cos A is:
- A. cos A/sin A
- B. sin A/cos A
- C. 1/(sin A cos A)
- D. sin A + cos A
Answer: B. sin A/cos A
The identity tan A = sin A/cos A is a basic trigonometric relation.
The identity tan A = sin A/cos A is a basic trigonometric relation.
In a right triangle, for an acute angle A, the side opposite A is 3 cm and the hypotenuse is 5 cm. What is sin A?
- A. 3/5
- B. 4/5
- C. 3/4
- D. 5/3
Answer: A. 3/5
sin A = opposite side/hypotenuse = 3/5.
sin A = opposite side/hypotenuse = 3/5.
If sin A + cos A = √2 for an acute angle A, then tan A + cot A is:
- A. 1
- B. 2
- C. √2
- D. 4
Answer: B. 2
Squaring sin A + cos A = √2 gives 1 + 2 sin A cos A = 2, so sin A cos A = 1/2. Thus tan A + cot A = 1/(sin A cos A) = 2.
Squaring sin A + cos A = √2 gives 1 + 2 sin A cos A = 2, so sin A cos A = 1/2. Thus tan A + cot A = 1/(sin A cos A) = 2.
If tan θ + sec θ = p, then (1 - sin θ)/(1 + sin θ) is equal to:
- A. p²
- B. 1/p²
- C. p
- D. 1/p
Answer: B. 1/p²
Since tan θ + sec θ = (1 + sin θ)/cos θ = p and sec θ - tan θ = 1/p, the ratio (1 - sin θ)/(1 + sin θ) = 1/p².
Since tan θ + sec θ = (1 + sin θ)/cos θ = p and sec θ - tan θ = 1/p, the ratio (1 - sin θ)/(1 + sin θ) = 1/p².