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If for real values of x, costheta=x+(1)/...

If for real values of x, `costheta=x+(1)/(x)`, then

A

`theta` is an acute angle

B

`theta` is right angle

C

`theta` is an obtuse angle

D

No value of `theta` is possible

Text Solution

Verified by Experts

The correct Answer is:
D
Here, `" "costheta=x+(1)/(x)`
`rArr" "costheta=(x^(2)+1)/(x)`
`" "x^(2)-xcostheta+1=0`
For real value of x, `(-costheta)^(2)-4xx1xx1=0`
`" "cos^(2)theta=4`
`" "costheta=pm2`
which is not possible. `" "[because-1lecosthetale1]`
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