NCERT Solutions for Class 10 Maths Chapter 8 Introduction to Trigonometry Exercise 8.1
NCERT Solutions for Maths Chapter 8, Exercise 8.1 involve complete answers for each question in the exercise 8.1. The solutions provide students a strategic methods to prepare for their exam. Class 10 Maths Chapter 8 Introduction to Trigonometry Exercise 8.1 questions and answers helps students to perform better in exam and it will clear doubts definitely. Students will find it extremely easy to understand the questions and learn solving the problems. NCERT Solutions for Chapter 8 Introduction to Trigonometry Exercise 8.1 prepared by www.mathematicsandinformationtechnology.com team in very delicate, easy and creative way.
Question 1:
In ΔABC right angled at B, AB = 24 cm, BC = 7 cm. Determine
(i)sin A, cos A
(ii)sin C, cos C
Solution 1:
Question 2:
In the given figure find tan P − cot R.
Solution 2:
Question 3:
If sin A =3/4, calculate cos A and tan A.
Solution 3:
Question 4:
Given 15 cot A = 8. Find sin A and sec A.
Solution 4:
Question 5:
Given sec θ = 13/12, calculate all other trigonometric ratios.
Solution 5:
Question 6:
If ∠A and ∠B are acute angles such that cos A = cos B, then show that ∠A = ∠B.
Solution 6:
Question 10:
In ΔPQR, right angled at Q, PR + QR = 25 cm and PQ = 5 cm. Determine the values of sin P, cos P and tan P.
Solution 10:
Question 11:
State whether the following are true or false. Justify your answer.
(i)The value of tan A is always less than 1.
(ii)sec A=12/5,for some value of angle A.
(iii)cos A is the abbreviation used for the cosecant of angle A.
(iv)cot A is the product of cot and A
(v)sin θ = 4/3, for some angle θ
Solution 11:
(i)False, because sides of a right angled triangle may have any length, So tan A may have any value.
(ii) sec A=12/5
True,as the value of Sec A > 1,
(iii)Abbreviation used for cosecant of ∠A is cosec A. And cos A is the abbreviation used for cosine of ∠A. Hence, the given statement is false.
(iv)Cot A is not the product of cot and A. It is the cotangent of ∠A.
‘Cot’ separated from ‘A’ has no meaning.
Hence, the given statement is false.
(v)Sin θ=4/3
We know that in a right-angled triangle,
Sin θ=perpendicular / Hypotenuse
In a right-angled triangle, hypotenuse is always greater than the remaining two sides.Also, the value of Sine should be less than 1 always. Therefore,such value of sin θ is not possible.
Hence,the given statement is false
State whether the following are true or false. Justify your answer.
(i)The value of tan A is always less than 1.
(ii)sec A=12/5,for some value of angle A.
(iii)cos A is the abbreviation used for the cosecant of angle A.
(iv)cot A is the product of cot and A
(v)sin θ = 4/3, for some angle θ
Solution 11:
(i)False, because sides of a right angled triangle may have any length, So tan A may have any value.
(ii) sec A=12/5
True,as the value of Sec A > 1,
(iii)Abbreviation used for cosecant of ∠A is cosec A. And cos A is the abbreviation used for cosine of ∠A. Hence, the given statement is false.
(iv)Cot A is not the product of cot and A. It is the cotangent of ∠A.
‘Cot’ separated from ‘A’ has no meaning.
Hence, the given statement is false.
(v)Sin θ=4/3
We know that in a right-angled triangle,
Sin θ=perpendicular / Hypotenuse
In a right-angled triangle, hypotenuse is always greater than the remaining two sides.Also, the value of Sine should be less than 1 always. Therefore,such value of sin θ is not possible.
Hence,the given statement is false
