Use Newton's method to approximate a root of the equation 5sin(x)=x as follows.
Let x1=1 be the initial approximation.
The second approximation x2 is -.8850033452
and the third approximation x3 is ?
I got 2.377647049 but it was wrong

Question

Use Newton's method to approximate a root of the equation 5sin(x)=x as follows. 
Let x1=1 be the initial approximation. 
The second approximation x2 is -.8850033452 
and the third approximation x3 is ?
I got 2.377647049 but it was wrong

anonymous · Answer

f(x)=5sin(x) - x
f'(x) = 5cos(x) - 1

x3 = -.8850033452  - f(-.885)/f'(-.885)

anonymous · Answer

-.8850033452 - (5*Sin[-.8850033452] + .8850033452)/(5*
     Cos[-.8850033452] - 1) = 0.492644

anonymous · Answer

thanks! ^-^

anonymous · Answer

i see what you did

anonymous · Answer

you did 1- f(x2)/f'(x2) instead of x2 - f(x2)/f'(x2)