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I was doing an example of Bisection method applied to $f(x) = \cos(x) - xe^{x}= 0$,enter image description here

I did all correctly upto 4th step , but after that i don't understand how it is considering the interval of $(0.5,0531)$ as i am getting it to be $(0.562,0.625)$ as $f(0.562)>0$ and $f(0.625)<0$ , and i saw other sources the answer is still coming to be $0.517$

Any ideas or help!

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    Your chart specifically says $f(0.562)<0$, which is why it is used as the new right endpoint in step 5, with the left endpoint still being 0.5. (since you haven't found another point with $f>0$ yet). – 2017-02-24
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    If you check by calculator $f(0.562) > 0$ and $f(0.625) < 0$? – 2017-02-24
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    >> cos(0.562)-0.562*exp(0.562) ans = -0.1397 That said I technically misspoke: the chart says $f(0.5) f(0.562)<0$, but $f(0.5)>0$, so it therefore says $f(0.562)<0$ as I originally said. – 2017-02-24
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    Is the agument in cosine term radian or in degree ? – 2017-02-24
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    As when i use my fx-991MS it gives positive and when i google it , it gives me negative? – 2017-02-24
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    Google gives $\cos(0.562) = 0.84619104481$ , fx-991MS gives $\cos(0.562) = 0.999951894$...?? – 2017-02-24
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    Barring additional context, you should generally assume trig functions are measured in radians. – 2017-02-24

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