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1. Bisection method example ( Enter your problem )
  1. Algorithm & Example-1 `f(x)=x^3-x-1`
  2. Example-2 `f(x)=2x^3-2x-5`
  3. Example-3 `x=sqrt(12)`
  4. Example-4 `x=root(3)(48)`
  5. Example-5 `f(x)=x^3+2x^2+x-1`

3. Example-3 `x=sqrt(12)`





Find `sqrt(12)` using Bisection method

Solution:
Let `x=sqrt(12)`

`:.x^2=12`

`:.x^2-12=0`

i.e. `f(x)=x^2-12`

Here
`x`01234
`f(x)`-12-11-8-34



`1^(st)` iteration :

Here `f(3) = -3 < 0` and `f(4) = 4 > 0`

`:.` Now, Root lies between `3` and `4`

`x_0=(3+4)/2=3.5`

`f(x_0)=f(3.5)=3.5^2-12=0.25 > 0`


`2^(nd)` iteration :

Here `f(3) = -3 < 0` and `f(3.5) = 0.25 > 0`

`:.` Now, Root lies between `3` and `3.5`

`x_1=(3+3.5)/2=3.25`

`f(x_1)=f(3.25)=3.25^2-12=-1.4375 < 0`


`3^(rd)` iteration :

Here `f(3.25) = -1.4375 < 0` and `f(3.5) = 0.25 > 0`

`:.` Now, Root lies between `3.25` and `3.5`

`x_2=(3.25+3.5)/2=3.375`

`f(x_2)=f(3.375)=3.375^2-12=-0.6094 < 0`


`4^(th)` iteration :

Here `f(3.375) = -0.6094 < 0` and `f(3.5) = 0.25 > 0`

`:.` Now, Root lies between `3.375` and `3.5`

`x_3=(3.375+3.5)/2=3.4375`

`f(x_3)=f(3.4375)=3.4375^2-12=-0.1836 < 0`


`5^(th)` iteration :

Here `f(3.4375) = -0.1836 < 0` and `f(3.5) = 0.25 > 0`

`:.` Now, Root lies between `3.4375` and `3.5`

`x_4=(3.4375+3.5)/2=3.4688`

`f(x_4)=f(3.4688)=3.4688^2-12=0.0322 > 0`


`6^(th)` iteration :

Here `f(3.4375) = -0.1836 < 0` and `f(3.4688) = 0.0322 > 0`

`:.` Now, Root lies between `3.4375` and `3.4688`

`x_5=(3.4375+3.4688)/2=3.4531`

`f(x_5)=f(3.4531)=3.4531^2-12=-0.0759 < 0`


`7^(th)` iteration :

Here `f(3.4531) = -0.0759 < 0` and `f(3.4688) = 0.0322 > 0`

`:.` Now, Root lies between `3.4531` and `3.4688`

`x_6=(3.4531+3.4688)/2=3.4609`

`f(x_6)=f(3.4609)=3.4609^2-12=-0.0219 < 0`


`8^(th)` iteration :

Here `f(3.4609) = -0.0219 < 0` and `f(3.4688) = 0.0322 > 0`

`:.` Now, Root lies between `3.4609` and `3.4688`

`x_7=(3.4609+3.4688)/2=3.4648`

`f(x_7)=f(3.4648)=3.4648^2-12=0.0051 > 0`


`9^(th)` iteration :

Here `f(3.4609) = -0.0219 < 0` and `f(3.4648) = 0.0051 > 0`

`:.` Now, Root lies between `3.4609` and `3.4648`

`x_8=(3.4609+3.4648)/2=3.4629`

`f(x_8)=f(3.4629)=3.4629^2-12=-0.0084 < 0`


`10^(th)` iteration :

Here `f(3.4629) = -0.0084 < 0` and `f(3.4648) = 0.0051 > 0`

`:.` Now, Root lies between `3.4629` and `3.4648`

`x_9=(3.4629+3.4648)/2=3.4639`

`f(x_9)=f(3.4639)=3.4639^2-12=-0.0016 < 0`


`11^(th)` iteration :

Here `f(3.4639) = -0.0016 < 0` and `f(3.4648) = 0.0051 > 0`

`:.` Now, Root lies between `3.4639` and `3.4648`

`x_10=(3.4639+3.4648)/2=3.4644`

`f(x_10)=f(3.4644)=3.4644^2-12=0.0018 > 0`


`12^(th)` iteration :

Here `f(3.4639) = -0.0016 < 0` and `f(3.4644) = 0.0018 > 0`

`:.` Now, Root lies between `3.4639` and `3.4644`

`x_11=(3.4639+3.4644)/2=3.4641`

`f(x_11)=f(3.4641)=3.4641^2-12=0.0001 > 0`


Approximate root of the equation `x^2-12=0` using Bisection method is `3.4641` (After 12 iterations)

`n``a``f(a)``b``f(b)``c=(a + b)/2``f(c)`Update
13-3443.50.25`b = c`
23-33.50.253.25-1.4375`a = c`
33.25-1.43753.50.253.375-0.6094`a = c`
43.375-0.60943.50.253.4375-0.1836`a = c`
53.4375-0.18363.50.253.46880.0322`b = c`
63.4375-0.18363.46880.03223.4531-0.0759`a = c`
73.4531-0.07593.46880.03223.4609-0.0219`a = c`
83.4609-0.02193.46880.03223.46480.0051`b = c`
93.4609-0.02193.46480.00513.4629-0.0084`a = c`
103.4629-0.00843.46480.00513.4639-0.0016`a = c`
113.4639-0.00163.46480.00513.46440.0018`b = c`
123.4639-0.00163.46440.00183.46410.0001`b = c`







This material is intended as a summary. Use your textbook for detail explanation.
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