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Question
Find the direction cosines of the line
`(x+2)/2=(2y-5)/3; z=-1`
Solution
Equation of line is `(x+2)/2=(2y-5)/3;z=-1`
`(x+2)/2=(y-5/2)/(3/2)=(z+1)/1`
Direction ratios of the line are 2, 3/2, 1.
∴Direction cosines of the line are
`2/(sqrt(4+(9/4)+1)),(3/2)/sqrt(4+9/4+1),1/sqrt(4+9/4+1)`
`i.e 2/(1/2sqrt(29/4)),(3/2)/(1/2sqrt(29/4)),1/(1/2sqrt(29/4)) `
`4/sqrt(29),3/sqrt(29),2/sqrt(29)`
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