This is the concept of algebra, to solve the expression we proceed as follows;
cos 2x-cosx=0
cos 2x=cosx
but:
cos 2x+1=2(cos^2x)
thereore;
from:
cos 2x=cos x
adding 1 on both sides we get:
cos 2x+1=cos x+1
2(cos^2x)=cosx+1
suppose;
cos x=a
thus;
2a^2=a+1
a^2-1/2a-1/2=0
solving the above quadratic we get:
a=-0.5 and a=1
when a=-0.5
cosx=-0.5
x=120=2/3π
when x=1
cos x=1
x=0
the answer is:
x=0 or x=2/3π
Answer:
m∡A = 100°
m∡B = 50°
m∡C = 30°
Step-by-step explanation:
let 'x' = m∡B; 50°
let '2x' = m∡A; 100°
let 'x-20' = m∡C; 30°
x + 2x + x - 20 = 180
4x - 20 = 180
4x = 200
x = 50
Do 36 divided by the amount of sides the hexagon has. I think I am not sure
