Assertion and Reason Questions for Class 10 Maths Chapter 8 Introduction to Trigonometry PDF

Assertion and Reason Questions for Class 10 Maths Chapter 8 Introduction to Trigonometry are available in this Maths article. Assertion and Reason Questions for Class 10 Maths Chapter 8 Introduction to Trigonometry are very useful to solve the problems easily. This article helps the students to know the key questions and answers about Introduction to Trigonometry. Trigonometry covers trigonometric ratios, values of angles, identities, and relationships between sine, cosine, tangent, secant, cosecant, and cotangent, which are important in exam practice. Our subject experts have provided detailed solutions for these problems based on the CBSE syllabus and the NCERT textbook. This material helps students revise the chapter easily and perform well in the final examination. A free downloadable PDF is also available for easy practice and revision.

Important Assertion And Reason Questions On Introduction To Trigonometry

Directions: In the following questions a statement of assertion (A) is followed by a statement of reason(R). Mark the correct choice as:

Choose the correct option for the following questions:

  • (A). Both Assertion (A) and Reason (R) are true, and Reason is the correct explanation of Assertion.

  • (B). Both Assertion (A) and Reason (R) are true, but Reason is not the correct explanation of Assertion.

  • (C). Assertion (A) is true, but Reason (R) is false.

  • (D). Assertion (A) is false, but Reason (R) is true.

Question 1:

Assertion (A): Trigonometric ratios are defined with respect to the angles of a right triangle.

Reason (R): A right triangle contains one angle equal to (90^\circ).

Options:

(A). Both A and R are true, and R is the correct explanation of A.
(B). Both A and R are true, but R is not the correct explanation of A.
(C). A is true, but R is false.
(D). A is false, but R is true.

Correct Answer: (B). Both A and R are true, but R is not the correct explanation of A.

Question 2:

Assertion (A): The value ofsin30\sin 30^\circis12\frac{1}{2}.

Reason (R): In a30609030^\circ-60^\circ-90^\circtriangle, the side opposite to3030^\circis half the hypotenuse.

Options:

(A). Both A and R are true, and R is the correct explanation of A.
(B). Both A and R are true, but R is not the correct explanation of A.
(C). A is true, but R is false.
(D). A is false, but R is true.

Correct Answer: (A). Both A and R are true, and R is the correct explanation of A.

Question 3:

Assertion (A): The value ofcos0\cos 0^\circis 1.

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Reason (R): The side adjacent to angle00^\circis equal to the hypotenuse.

Options:

(A). Both A and R are true, and R is the correct explanation of A.
(B). Both A and R are true, but R is not the correct explanation of A.
(C). A is true, but R is false.
(D). A is false, but R is true.

Correct Answer: (A). Both A and R are true, and R is the correct explanation of A.

Question 4:

Assertion (A): The value oftan45\tan 45^\circis 1.

Reason (R): In a45459045^\circ-45^\circ-90^\circtriangle, the opposite side and adjacent side are equal.

Options:

(A). Both A and R are true, and R is the correct explanation of A.
(B). Both A and R are true, but R is not the correct explanation of A.
(C). A is true, but R is false.
(D). A is false, but R is true.

Correct Answer: (A). Both A and R are true, and R is the correct explanation of A.

Question 5:

Assertion (A):

The trigonometric ratiosinθ\sin \thetais given by:

sinθ=PerpendicularHypotenuse\sin\theta=\frac{\text{Perpendicular}}{\text{Hypotenuse}}

Reason (R): The hypotenuse is the longest side of a right triangle.

Options:

(A). Both A and R are true, and R is the correct explanation of A.
(B). Both A and R are true, but R is not the correct explanation of A.
(C). A is true, but R is false.
(D). A is false, but R is true.

Correct Answer: (B). Both A and R are true, but R is not the correct explanation of A.

Question 6:

Assertion (A): The value ofsec0\sec 0^\circis 1.

Reason (R):secθ\sec \theta is the reciprocal ofcosθ\cos \theta.

Options:

(A). Both A and R are true, and R is the correct explanation of A.
(B). Both A and R are true, but R is not the correct explanation of A.
(C). A is true, but R is false.
(D). A is false, but R is true.

Correct Answer: (A). Both A and R are true, and R is the correct explanation of A.

sec0=1cos0=11=1\sec 0^\circ=\frac{1}{\cos 0^\circ}=\frac{1}{1}=1

Question 7:

Assertion (A): The value of cosec90\cosec 90^\circ is 1.

Reason (R):cosecθ\cosec \theta is the reciprocal ofsinθ\sin \theta.

Options:

(A). Both A and R are true, and R is the correct explanation of A.
(B). Both A and R are true, but R is not the correct explanation of A.
(C). A is true, but R is false.
(D). A is false, but R is true.

Correct Answer: (A). Both A and R are true, and R is the correct explanation of A.

Question 8:

Assertion (A):tan0=0\tan 0^\circ = 0

Reason (R):tanθ=sinθcosθ\tan \theta = \frac{\sin \theta}{\cos \theta}

Options:

(A). Both A and R are true, and R is the correct explanation of A.
(B). Both A and R are true, but R is not the correct explanation of A.
(C). A is true, but R is false.
(D). A is false, but R is true.

Correct Answer: (A). Both A and R are true, and R is the correct explanation of A.

Question 9:

Assertion (A): The value ofsin2θ+cos2θ\sin^2\theta+\cos^2\theta is always 1.

Reason (R): This is a fundamental trigonometric identity.

sin2θ+cos2θ=1\sin^2\theta+\cos^2\theta=1

Options:

(A). Both A and R are true, and R is the correct explanation of A.
(B). Both A and R are true, but R is not the correct explanation of A.
(C). A is true, but R is false.
(D). A is false, but R is true.

Correct Answer: (A). Both A and R are true, and R is the correct explanation of A.

Question 10:

Assertion (A):tanθ\tan \theta is undefined forθ=90\theta=90^\circ.

Reason (R):cos90=0\cos 90^\circ = 0.

Options:

(A). Both A and R are true, and R is the correct explanation of A.
(B). Both A and R are true, but R is not the correct explanation of A.
(C). A is true, but R is false.
(D). A is false, but R is true.

Correct Answer: (A). Both A and R are true, and R is the correct explanation of A.

Question 11:

Assertion (A): The value ofcot45\cot 45^\circis 1.

Reason (R):  cotθ\cot \thetais the reciprocal oftanθ\tan \theta.

Options:

(A). Both A and R are true, and R is the correct explanation of A.
(B). Both A and R are true, but R is not the correct explanation of A.
(C). A is true, but R is false.
(D). A is false, but R is true.

Correct Answer: (A). Both A and R are true, and R is the correct explanation of A.

Question 12:

Assertion (A):sin90=1\sin 90^\circ = 1

Reason (R): The perpendicular side becomes equal to the hypotenuse at9090^\circ.

Options:

(A). Both A and R are true, and R is the correct explanation of A.
(B). Both A and R are true, but R is not the correct explanation of A.
(C). A is true, but R is false.
(D). A is false, but R is true.

Correct Answer: (A). Both A and R are true, and R is the correct explanation of A.

Question 13:

Assertion (A):secθ=1cosθ\sec \theta=\frac{1}{\cos \theta}

Reason (R): Secant is the reciprocal ratio of cosine.

Options:

(A). Both A and R are true, and R is the correct explanation of A.
(B). Both A and R are true, but R is not the correct explanation of A.
(C). A is true, but R is false.
(D). A is false, but R is true.

Correct Answer: (A). Both A and R are true, and R is the correct explanation of A.

Question 14:

Assertion (A): The value ofcos60\cos 60^\circis12\frac{1}{2}.

Reason (R): In a 30609030^\circ-60^\circ-90^\circ triangle, the adjacent side to  6060^\circ is half the hypotenuse.

Options:

(A). Both A and R are true, and R is the correct explanation of A.
(B). Both A and R are true, but R is not the correct explanation of A.
(C). A is true, but R is false.
(D). A is false, but R is true.

Correct Answer: (A). Both A and R are true, and R is the correct explanation of A.

Question 15:

Assertion (A):tanθ=sinθcosθ\tan \theta = \frac{\sin \theta}{\cos \theta}

Reason (R): Division of the sine ratio by the cosine ratio gives the tangent ratio.

Options:

(A). Both A and R are true, and R is the correct explanation of A.
(B). Both A and R are true, but R is not the correct explanation of A.
(C). A is true, but R is false.
(D). A is false, but R is true.

Correct Answer: (A). Both A and R are true, and R is the correct explanation of A.

Download PDF - Assertion And Reason Questions For Class 10 Maths Chapter 8 Introduction To Trigonometry

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Frequently Asked Questions on Introduction To Trigonometry Class 10 Chapter 8 Assertion And Reason Questions

1. What is Trigonometry?

Trigonometry is the branch of mathematics that studies relationships between angles and sides of triangles.

2. What are the six trigonometric ratios?

The six trigonometric ratios are:

  • Sine (sin)
  • Cosine (cos⁡)
  • Tangent (tan⁡)
  • Cosecant (cosec)
  • Secant (sec)
  • Cotangent (cot)

3. What is the sine ratio?

sinθ=PerpendicularHypotenuse\sin\theta=\frac{\text{Perpendicular}}{\text{Hypotenuse}}

4. What is the cosine ratio?

cosθ=BaseHypotenuse\cos\theta = \frac{\text{Base}}{\text{Hypotenuse}}

5. What is the tangent ratio?

tanθ=PerpendicularBase\tan\theta = \frac{\text{Perpendicular}}{\text{Base}}

6. What are complementary trigonometric ratios?

sin(90𝜃)=cos⁡𝜃sin ⁡ ( 90 ∘ − 𝜃 ) = cos ⁡ 𝜃

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