Question

solve it any One hkdsjkskskakskakksmsmsmsmsmsmsmsms​

Answer 1

Step-by-step explanation:

Answer

Let OP be any line through the origin O which has direction cosines l,m,n.

Let P be the point having coordinates (x,y,z) and OP=r.

Then OP

2

=x

2

+y

2

+z

2

=r

2

...(1)

From P draw PA,PB,PC perpendicular on the coordinate axes, so that OA=x,OB=y,OC=z

Also, ∠POA=α,∠POB=β,∠POC=γ

From triangle AOP,l=cosα=

r

x

⇒x=lr

Similarly, y=mr,z=nr

Adding all we getx

2

+y

2

+z

2

=r

2

(l

2

+m

2

+n

2

)

⇒r

2

=r

2

(l

2

+m

2

+n

2

)

⇒l

2

+m

2

+n

2

=1

Answer 2

Step-by-step explanation:

9).Answer :- i). l:m = 1¼

Hope its help..