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we use regula falsi method for numerical analysis such as for equations like this

x^3 + x^2 + 1 = 0. As you can see, regula falsi works like a secant method. The roots of that equation are the values of x that makes the function equal to zero..

Now, how can we modify regula falsi method so that, it can solve equations like below

enter image description here

lets say, V = 40, g = 9.8 , c = 14 and let m = x. now this can be compared to the equation like x^3 + x^2 + 1 = 40, (we simply equate the whole equation to some constant, not zero)

the problem is, when we use the unmodified regula falsi, we end up the iteration below (notice that it doesnt converge, there somethings wrong in the original regula falsi)

enter image description here

how can we make regula falsi work above, the problem i think is that the x2 is not on the y = 0, but on the y = 40. thanks how can we modify this original method? enter image description here

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Subtract $V$ on both sides; then you have something equals zero.

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without subtracting V on both sides, how can we modify the method itself. – WantIt Oct 28 '12 at 14:26
this is the original method. – WantIt Oct 28 '12 at 14:28
@vvavepacket: I don't understand the distinction you make between modifying the equation and modifying the method; please explain. – joriki Oct 28 '12 at 14:39

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