If `costheta=12/13`, ``0 < `theta` < `pi`/2``, find the value of `frac(1)(tan^2theta)`

If sintheta=12/13 0<(theta)<(pi/2)) and cosphi=-3/5 (pi<(phi)<(3pi)/2) then sin(theta + phi ) will be

If costheta=(-1)/(2)and0^(@)ltthetalt360^(@) , then the values of theta are

If sec theta = 13/12, find values of other trigonometric ratios.

If cosec theta = (13)/(12) , then find the values of cot theta and sin theta .

If sintheta+ costheta=1 , then find the general value of theta .

Find the inverse of A = [[costheta,-sintheta, 0],[sintheta, costheta, 0],[0,0,1]] by elementary column transformations.

Find the inverse of A = [[costheta,-sintheta, 0],[sintheta, costheta, 0],[0,0,1]] (i) elementary row transformations.

If A=[(cos theta,sin theta,0),(-sin theta,cos theta,0),(0,0,1)] , where A_(11), A_(12), A_(13) are co-factores of a_(11), a_(12), a_(13) respectively, then the value of a_(11)A_(11)+a_(12)A_(12)+a_(13)A_(13)=