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Question : 59 of 160
Marks:
+1,
-0
Solution:
Given,
(3,0,2) and
(0,2,k) are the direction ratios of two lines and
θ is the angle between them.
‌∴cos‌θ=‌| 3×0+0×2+2×k |
| √32+02+22⋅√02+22+k2 |
‌⇒|cos‌θ|=|‌|‌⇒|‌|=‌[‌ given, ‌|cos‌θ|=‌]‌⇒‌‌‌=(‌)2⇒‌=‌‌⇒‌‌52k2=144+36k2‌⇒‌‌16k2=144⇒k2=9‌⇒‌‌k=±3
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