Acute angle between two lines with slopes m and `m_(2)` is given by `tantheta=|(m_(2)-m_(1))/(1+m_(1)m_(2))|`

If theta is the acute angle between the lines with slopes m1 and m2 then tan theta=(m_(1)-m_(2))/(1+m_(1)m_(2)) 2) if p is the length the perpendicular from point P(x1,y1) to the line ax +by+c=0 then p=(ax_(1)+by_(1)+c)/(sqrt(a^(2)+b^(2)))

The gravitational force between two point masses m_(1) and m_(2) at separation r is given by F = k(m_(1) m_(2))/(r^(2)) The constant k doesn't

The acute angle between the two lines whose d.cs are given by l+m-n=0 and l^(2)+m^(2)-n^(2)=0 is

The gravitional force between two point masses m_(1) and m_(2) at separation r is given by F=k (m_(1)m_(2))/r^(2) The constant k

If the direction cosines of two lines are (l_(1), m_(1), n_(1)) and (l_(2), m_(2), n_(2)) and the angle between them is theta then l_(1)^(2)+m_(1)^(2)+n_(1)^(2)=1=l_(2)^(2)+m_(2)^(2)+n_(2)^(2) and costheta = l_(1)l_(2)+m_(1)m_(2)+n_(1)n_(2) If the angle between the lines is 60^(@) then the value of l_(1)(l_(1)+l_(2))+m_(1)(m_(1)+m_(2))+n_(1)(n_(1)+n_(2)) is

STATEMENT-1 : If a line making an angle pi//4 with x-axis, pi//4 with y-axis then it must be perpendicular to z-axis and STATEMENT-2 : If direction ratios of two lines are l_(1), m_(1), n_(1) and l_(2), m_(2), n_(2) then the angle between them is given by theta = cos ^(-1)(l_(1)l_(2)+m_(2)m_(2)+n_(1)n_(2))

The direction cosines of the lines bisecting the angle between the lines whose direction cosines are l_(1),m_(1),n_(1) and l_(2),m_(2),n_(2) and the angle between these lines is theta, are

The direction cosines of the lines bisecting the angle between the lines whose direction cosines are I_(1),m_(1),n_(1) and I_(2),m_(2),n_(2) and the angle between these lines is theta ,are

If theta is the angle between two lines whose d.c's are (l_(1),m_(1),n_(1)) and (l_(2),m_(2),n_(2)) then the lines are perpendicular if and only if