**Trigonometry Identities**

Let us take any acute angle taking point P on OB we draw perpendicular PQ on OAB. Thus we have a right angled triangle OPQ. If we suppose

We have OQ

^{2}+ PQ^{2}= OP^{2}--------------(1)Dividing both sides of (i) by OP

^{2}we getSimilarly, dividing both sides of (1) by OQ

^{2}we getA gain dividing both sides of (i) by PQ

^{2}, we getHere, (2), (3) and (4) are all identities. These can be used to express one trigonometric ratio to other trigonometric ratio. For example:

Similarly,

Subjects |
Maths (Part-1) by Mr. M. P. Keshari |

Chapter 9 |
Circle |

Chapter 10 |
Tangents to a circle |

Chapter 11 |
Geometrical Construction |

Chapter 12 |
Troigonometry |

Chapter 13 |
Height and Distance |

Chapter 14 |
Mensuration |

Chapter 15 |
Statistics |

Chapter 16 |
Probability |

Chapter 17 |
Co-ordinate Geometry |