Q3 of 76 Page 467

If a line has the direction ratios –18, 12, –4, then what are its direction cosines?

If the direction ratios of the line are a, b and c

Then the direction cosines are


Given direction ratios are – 18, 12 and – 4


⇒ a= -18, b = 12 and c= -4



=


=


Direction cosines are




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