Help needed with direction angles and vector equations

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To determine the vector equation of a line with direction angles of 60°, 45°, and 60° passing through the point (1, -2, 5), one must utilize trigonometric ratios to find the direction cosines. The direction cosines can be calculated using the cosine of the given angles, which will form a unit vector. This unit vector, combined with the point through which the line passes, will allow for the formulation of the vector equation. The poster expresses frustration after a week of unsuccessful attempts to solve the problem and seeks assistance as a last resort. Clarity on the relationship between trigonometry and vector equations is essential for solving this homework question.
agenttiny200
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Homework Statement



A line has direction angles 60°, 45°, 60° and passes through the point
(1, -2, 5). Determine the vector equation of this line.

Homework Equations



I honestly have no clue. My teacher gave a hint it has to do with trig (as in the trig ratios) and the unit vector formula, but I don't see how they mix.

The Attempt at a Solution



Tried everything except the right way for the last week, resulting in dead ends.
 
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if no one has a clue, it would help to mention that, proving to my teacher that he should just give me the answer.
 
And I am serious when I say I have been trying for a week to solve it, I am not trying to get by easily. posting my questions here is kind of a last resort, for a question that I am really stuck on.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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