Question

triangle
Three wires of length , la, lb and lc form triangle
surmounted by
by another circular
wire If lc is
diameter lc = 21 then
then the
angle between la and lb , will be​

Answer 1

Answer:

Here, AB=l  1  ,BC=l  3  and AC=l 2

l  3=2 l 1 ​             [ Given ]

If l3  is the diameter of a circle then the △ABC is right-angled triangle.

As angle form in semicircle is right angled.

⇒  cosB= l 1 /l 3= l  1 /2l  1 = 1 /2

⇒  cosB= 1 /2

⇒  B=cos^−1 1/2=60°

∴  The angle between l1   and l 3  will be 60 °