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If a line makes angles 90°, 135°, 45° with x, y and z-axes...

If a line makes angles 90°, 135° | Class 12 Mathematics Chapter Three Dimensional Geometry, Three Dimensional Geometry NCERT Solutions

Question:

If a line makes angles 90°, 135°, 45° with x, y and z-axes respectively, find its direction cosines.

Answer:

Let direction cosines of the line be l, m, and n.

\begin{align}l = cos90^0=0\end{align}

\begin{align}m = cos135^0=-\frac{1}{\sqrt{2}}\end{align}

\begin{align}n = cos45^0=\frac{1}{\sqrt{2}}\end{align}

\begin{align}Therefore, the\; direction\; cosines\; of \;the\; line\; are\;0, -\frac{1}{\sqrt{2}}\;and\;\frac{1}{\sqrt{2}}\end{align}

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Welcome to the NCERT Solutions for Class 12 Mathematics - Chapter . This page offers a step-by-step solution to the specific question from Excercise 1 , Question 1: If a line makes angles 90°, 135°, 45° with x, y and z-axes respectively, find its direct....

If a line makes angles 90°, 135° | Class 12 Mathematics Chapter Three Dimensional Geometry, Three Dimensional Geometry NCERT Solutions

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