[" (2) "cos^(2)theta(1+tan^(2)theta)=1],[" solution: "]

(1-cos^2theta)sec^2 theta= tan^2 theta

cos 2 theta is not equal to ................... A) 2 cos ^(2) theta -1 B) 1- 2 sin ^(2) theta C) (1+ tan ^(2) theta)/( 1- tan ^(2) theta) D) (1- tan ^(2) theta)/(1+ tan ^(2) theta)

Prove that : (1 - tan^(2) theta)/(1 + tan^(2) theta) = cos^(2) theta - sin^(2) theta

If theta=30o, verify that: ( i )cos2 theta=(1-tan^(2)theta)/(1+tan^(2)theta)( ii) cos3 theta=4cos^(3)theta-3cos theta

Prove that (1 - tan^(2) theta)/(1 + tan^(2) theta) = cos^(2) - sin^(2) theta

Show that (cos^(2)theta - sin^(2)theta)=(2tan theta)/((1- tan^(2)theta)) is not an identity .

sqrt((1-cos^(2)theta)sec^(2)theta)=tan theta

If tan^(2)theta + cos2theta=1 , then the general solution of theta is-

By using above basic addition/ subtraction formulae, prove that (i) tan (A+B)=(tan A+tan B)/(1-tan A tan B) , (ii) tan (A-B)=(tan A-tanB)/(1+tan A tan B) (iii) sin2theta=2sintheta costheta , (iv) cos2theta=cos^(2)theta=1-2sin^(2)theta=2cos^(2)theta-1 (v) tan 2theta=(2 tan theta)/(1-tan^(2) theta)