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The equation of line are 5x-3 = 15y + 7 = 3 - 10z. Write the direction cosines of the line. |
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Answer» `5x-3=15y+7=3-10z` `5(x-3/5)=15(y+7/5)=-10(z-3/10)` `(x-3/5)/(1/5)=(y+7/15)/(1/15)=(z-3/10)/(-1/10)` `l:m:n=1/5:1/15:-1/10=6:2:-3` `sqrt(l^2+m^2+n^2)=sqrt(6^2+2^2+3^2)=7` `cosalpha=6/7,alpha=cos^(-1)(6/7)` `cosbeta-2/7=beta=cos^(-1)(2/7)` `cosgamma=-3/7=gamma=cos^(-1)(-3/7)` `=(6/7,2/7,-3/7)`. |
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