Chapter 3 Trigonometric Functions Ex-3.1 |
Chapter 3 Trigonometric Functions Ex-3.3 |
Chapter 3 Trigonometric Functions Ex-3.4 |

**Answer
1** :

**Answer
2** :

It is given that

sin x = 3/5

We can write it as

We know that

sin^{2} x+ cos^{2} x = 1

We can write it as

cos^{2} x= 1 – sin^{2} x

**Answer
3** :

It is given that

cot x = 3/4

We can write it as

We know that

1 + tan^{2} x= sec^{2} x

We can write it as

1 + (4/3)^{2} =sec^{2} x

Substituting thevalues

1 + 16/9 = sec^{2} x

cos^{2} x= 25/9

sec x = ± 5/3

Here x lies in thethird quadrant so the value of sec x will be negative

sec x = – 5/3

We can write it as

**Answer
4** :

It is given that

sec x = 13/5

We can write it as

We know that

sin^{2} x+ cos^{2} x = 1

We can write it as

sin^{2} x= 1 – cos^{2} x

Substituting thevalues

sin^{2} x= 1 – (5/13)^{2}

sin^{2} x= 1 – 25/169 = 144/169

sin^{2} x= ± 12/13

Here x lies in thefourth quadrant so the value of sin x will be negative

sin x = – 12/13

We can write it as

**Answer
5** :

It is given that

tan x = – 5/12

We can write it as

We know that

1 + tan^{2} x= sec^{2} x

We can write it as

1 + (-5/12)^{2} =sec^{2} x

Substituting thevalues

1 + 25/144 = sec^{2} x

sec^{2} x= 169/144

sec x = ± 13/12

Here x lies in thesecond quadrant so the value of sec x will be negative

sec x = – 13/12

We can write it as

**Answer
6** :

We know that values ofsin x repeat after an interval of 2π or 360°

So we get

By further calculation

= sin 45^{o}

= 1/ √ 2

**Answer
7** :

We know that values ofcosec x repeat after an interval of 2π or 360°

So we get

By further calculation

= cosec 30^{o} =2

**Answer
8** :

We know that values oftan x repeat after an interval of π or 180°

So we get

By further calculation

We get

= tan 60^{o}

= √3

**Answer
9** :

We know that values ofsin x repeat after an interval of 2π or 360°

So we get

By further calculation

**Answer
10** :

We know that values oftan x repeat after an interval of π or 180°

So we get

By further calculation

Name:

Email:

Copyright 2017, All Rights Reserved. A Product Design BY CoreNet Web Technology