Main 2013 | JEE 2013 | Discussion Page

Distance between two parallel planes 2x+y+2z=8 and 4x+2y+a=4z+5=0 is

$\frac{3}{2}$

$\frac{5}{2}$

$\frac{7}{2}$

$\frac{9}{2}$

Option C

Given planes are

2x+y+2z-8=0

and 2x+y+2z+ $\frac{5}{2}$ =0

Distance between two planes

= $\frac{|c_{1}-c_{2}|}{\sqrt{a^{2}+b^{2}+c^{2}}}=|\frac{-8-\frac{5}{2}}{\sqrt{2^{2}+1^{2}}+2^{2}}|$

= $\frac{\frac{21}{2}}{3}=\frac{7}{2}$

Discussion Forum