State true or false.
(i) Value of `sin^2 5\theta + cos^2 5\theta` is 5.
(ii) The maximum value of `sin 3\theta` is 3.
(iii) If `0^\circ \lt \theta \lt \90^\circ`, then, `sin \theta + cos \theta \gt 1`.
(iv) If `0^\circ \lt \theta \le \90^\circ`, then maximum value of `5 + sin \theta` is 7.
(v) If `sin (A+B) = cos (A-B) = 1`, then `A=B=\pi/4`.
(vi) For any angle `\theta`, value of `cos \theta` may be `3/5`
(vii) If `\theta` is a positive acute angle, then value of `tan \theta` is always greater than 1.
(viii) Value of `(sin 12^\circ - cos 78^\circ)` is 1.