If `y =4sin^(2)theta-cos2theta`,then `y` lies in the interval

If A-2sin^(2)theta-cos2 theta, then A lies in the interval [-1,3](1,2](c)[-2,4](d) none of these

For -pi/2 lt theta lt pi/2, (sintheta + sin 2theta)/(1+costheta + cos2theta) lies in the interval

For -pi/2 lt theta lt pi/2, (sintheta + sin 2theta)/(1+costheta + cos2theta) lies in the interval

For -pi/2

For -(pi)/(2)

For -(pi)/(2)lttheta(pi)/(2),(sintheta+sin2theta)/(1+costheta+cos2theta) lies in the interval

If the equation cos^(4)theta+sin^(4) theta+lambda=0 has real solutions for theta , then lambda lies in the interval :

Delta=|(cos""(theta)/(2),1,1),(1,cos""(theta)/(2),-cos""(theta)/(2)),(-cos""(theta)/(2),1,1)| lies in the interval