# Trigonometry formulas for cbse 10th class

## Trigonometry formulas

Trigonometry is the science of relationships between the sides and angles of a right-angled triangle.

Ratios of sides of right triangle are called trigonometric ratios.
Consider triangle ABC right-angled at B. These ratios are always defined with respect to acute angle ‘A’ or angle ‘C. case I case II (i) sine A = $frac { perpendicular }{ hypotenuse } =frac { BC }{ AC }$ (i) sine C = $frac { perpendicular }{ hypotenuse } =frac { AB }{ AC }$ (ii) cosine A = $frac { base }{ hypotenuse } =frac { AB }{ AC }$ (ii) cosine C = $frac { base }{ hypotenuse } =frac { BC }{ AC }$ (iii) tangent A = $frac { perpendicular }{ base } =frac { BC }{ AB }$ (iii) tangent C = $frac { perpendicular }{ base } =frac { AB }{ BC }$ (iv) cosecant A = $frac { hypotenuse }{ perpendicular } =frac { AC }{ BC }$ (iv) cosecant C = $frac { hypotenuse }{ perpendicular } =frac { AC }{ AB }$ (v) secant A = $frac { hypotenuse }{ base } =frac { AC }{ AB }$ (v) secant C = $frac { hypotenuse }{ base } =frac { AC }{ BC }$ (v) cotangent A = $frac { base }{ perpendicular } =frac { AB }{ BC }$ (v) cotangent C = $frac { base }{ perpendicular } =frac { BC }{ AB }$

Trigonometric Ratios of Some Specific Angles Trigonometric Ratios of Complementary Angles  Trigonometric Identities   