Question

find the angle between the straight lines of x2 +4xy+3y2=0​

Answer 1

Answer:

Given : Equation of the pair of straight lines

3x

2

+4xy−3y

2

=0.

We know that the standard equation of the pair of straight lines is

ax

2

+2hxy+by

2

=0.

Comparing the given equation with the standard equation, we get

a=3,h=2 and b=−3

We also know that the relation for the angle between the pair of straight line (θ) is

tanθ=

a+b

2

h

2

−ab

=

3+(−3)

2

(2)

2

−(3)×(−3)

=∞

⇒θ=tan

−1

=(∞)=90

0