If the acute angle between the lines given by a x^2+2 h x y+b y^2=0 is 4 , then 4 h^2=

Step-by-step solution

As per data given we write 4 = | 2 h^2-a b a+b |=1 Squaring both sides, we get aligned & ( a + b )^2=4 ( ~h ^2- ab ) & 4 ~h ^2= a ^2+6 ab + b ^2 aligned