Question

if tan 0 = 20/ 21 thencos 0 -sin 0 / cos o + sin 0 is​

Answer 1

Answer

1/41

Step-by-step explanation:

tan theta=20/21

tan theta=perpendicular /base

perpendicular=20

base=21

Taking triangle ABC where AB is perpendicular , AC is the Hypotenuse and BC is the base respectively.

In triangle ABC

(Hypotenuse )^2 =(base)^2 + (perpendicular)^2

(AC)^2=(BC)^2+(AB)^2

(AC)^2=(21)^2+(20)^2

(AC)^2=441+400

(AC)^2=841

AC=square root 841

AC=41

sin theta =perpendicular/Hypotenuse

sin theta=20/41

cos theta=base/hypotenuse

cos theta=21/41

so,

cos theta -sin  theta /cos theta + sin theta

(21/41-20/41)/(21/41+20/41)

(21-20/41)/(21+20/41)

(21-20)*41/(21+20)/41

21-20/21+20

1/41