[cos theta],[" 8.Prove that the value of "sec^(2)theta+cos^(2)theta" can never "],[" be less than "2" ."]

Prove that sec^(2)theta+cos^(2)theta can never be less than 2.

Prove that sec^2 theta+ cos^2 theta can never be less than 2.

Prove that : cosec^2 theta+ sin^2 theta can never be less than 2.

Prove that : (i) sec theta+cos theta can never be equal to (3)/(2) (ii) cosec^(2)theta+"sin"^(2) theta can never be less than 2.

Consider the following statements : 1. "cos"theta+"sec"theta can never be equal to 1.5. 2. "sec"^(2)theta+"cosec"^(2)theta can never be less than 4. Which of the statements given above is/are correct ?

If sec theta + cos theta = 2 , then the value of sec^(2) theta + cosec^(2) theta is :

(i) Is the equation 2 cos^(2)theta + cos theta -6 =0 possible ? (ii) Is the equation 2 "sin"^(2)theta-costheta +4=0 can never be less than 2.

Prove that : sqrt((1-cos^(2)theta)sec^(2)theta)=tantheta