The minimum value of `cos^2 theta+ sec^2 theta` is – InterviewSolution

InterviewSolution

1.	The minimum value of `cos^2 theta+ sec^2 theta` is
Answer» We know, arithmatic mean of two terms is always greater than or equal to their geometric mean. `:. 1/2(cos^2theta+sec^2theta) ge (cos^2thetasec^2theta)^(1/2)` `=> (cos^2theta+sec^2theta) ge 2(cos^2theta*1/cos^2theta)^(1/2)` `=> (cos^2theta+sec^2theta) ge 2` So, minimum value of `cos^2theta+sec^2theta` is `2`.

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