# #y = sec^2theta + cos^2theta#, #theta != 0#, then?(Solve it without A.M - G.M inequality method)

##
A: y #=# 0

B: y #<=# 2

C: y #>=# -2

D: y #># 2

The answer is (D) for your reference

A: y

B: y

C: y

D: y

The answer is (D) for your reference

##### 1 Answer

Aug 2, 2017

#### Explanation:

#=sec^2theta-2secthetacostheta+cos^2theta+2#

#=(sectheta-costheta)^2+2#

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