#### Krushnaraj Pandya

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**1. The problem statement, all variables and given/known data**

A line makes some angle T with each of x and z axis, and angle U with y axis so that sin^2(U)=3sin^2(T).

**2. Relevant equations**

2cos^2(T)+cos^2(U)=1 .......(i)

cos^2(x)+sin^2(x)=1

**3. The attempt at a solution**

Using the above two eqns. give us the correct value for cos^2(T) which is 3/5 as per my textbook but plugging it back into (i) gives us cos^2(U)= -1/5. Am I wrong somewhere or is it a mistake in the book?