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A line makes angles theta,phiand Psi wit...

A line makes angles `theta,phiand Psi` with x,y,z axes respectively. Consider the following ltbRgt 1. `sin^2theta+sin^2phi=cos^2Psi`
2. `cos^2theta+cos^2phi=sin^2Psi`
3. `sin^2theta+cos^2phi=cos^2Psi`
Which of the above is/are correct?

A

1 only

B

2 only

C

3 only

D

2 and 3

Text Solution

Verified by Experts

The correct Answer is:
B
If a line makes angle `theta,phi and Psi" with "x,y,z` axes respectively, then
`cos^2theta+cos^2phi+cos^2Psi=1`
`rArr cos^2theta+cos^2phi=1-cos^2PsirArr cos^2theta+cos^2phi=sin^2Psi`
`:.` Statement (2) is correct.
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