Find the value of:
`(i)tan90^@`
`(ii) cos38^@cos52^@-sin38^@sin52^@`

cos38^(@)cos52^(@)-sin38^(@)sin52^(@)=0

Evaluate : cos 38^@ cos 52^@ - sin 38^@ sin 52^@ .

The value of cos38^(@)cos52^(@)-sin38^(@)sin52^(@) is :

Find the values of : (i) tan (-30^(@)) (ii) sin 120^(@) (iii) sin 135^(@) (iv) cos 150^(@) (v) sin 270^(@) (vi) cos 270^(@)

Find the values of: (i) tan (-30^(@)) (ii) sin 120^(@) (iii) sin 135^(@) (iv) cos 150^(@) (v) sin 270^(@) (vi) cos 270^(@)

Find the value of 2sin 30^@ +cos 0^@ +3 sin 90^@ .

Find the value of : (i) sin 30^(@)+cos 60^(@) (ii) sin 0^(@)-cos 0^(@) (iii) tan 45^(@)- tan 37^(@) (iv) sin 390^(@) (v) cos 405^(@) (vi) tan 420^(@) (vii) sin 150^(@) (viii) cos 120^(@) (ix) tan 135^(@) (x) sin (330^(@)) (xi) cos 300^(@) (xii) sin (-30^(@)) (xiii) cos (-60^(@)) (xiv) tan (-45^(@)) (xv) sin (-150^(@))

The value of sin^2 38^@-cos^2 52^@ is : sin^2 38^@-cos^2 52^@ का मान ज्ञात करें ।

(a) Find the value of followings : (i) sin 150^(@) , (ii) cos 135^(@) , (iii) cos (-30^(@)) , (iv) tan 225^(@) . (b) If cos theta =(4)/(5) . Find the value of sin theta and tan theta . (c) Find the value of sin ^(-1)(1) .

The value of cos52^(@)+cos68^(@)+cos172^(@) is