Applied Mathematics for Electrical Engineering (3130908)

BE | Semester-3   Winter-2019 | 26-11-2019

Q4) (c ( ii ))

Find a positive root of the equation x - cos x = 0 using bisection method correct to two places of decimals.

Let, fx = x - cos x
 
f0 = 0 - cos 0 = -1
 
f1 = 1 - cos 1 = 0.46
 
Therefore, root lies between 0,1 .
 
c =  a + b 2=  0 + 1 2 = 0.5
 
a<0 b>0 c x2
0 1 0.5 <0
0.5 1 0.75 >0
0.5 0.75 0.63 <0
0.63 0.75 0.69 <0
0.69 0.75 0.72 <0
0.72 0.75 0.74 <0
0.74 0.75 0.75 >0
0.74 0.75 0.75 -
 
x = 0.75 is the required root.