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ahmedelmorsi Group TitleBest ResponseYou've already chosen the best response.0
by parts
 2 years ago

ahmedelmorsi Group TitleBest ResponseYou've already chosen the best response.0
its equal x*cos(x)cos(x)
 2 years ago

guepardo14 Group TitleBest ResponseYou've already chosen the best response.0
Integral [ (sin(x)/x) dx ] The fact of the matter is, this integral is one that cannot be expressed in terms of elementary functions. There's no way we can solve this using the methods we know; we cannot use integration by parts, partial fractions, substitution, trigonometric substitution, etc to solve this. We can, however, approximate the integral through a power series. sin(x) has its own power series, so all we need to do is divide each term of the series by x (this represents (1/x)sin(x), or sin(x)/x) and then integrate thereafter. como: Your proposed solution doesn't work, and here's why. Let f(x) = (1/x)cos x  (1/x²)sinx + C To make it easier to differentiate, factor (1/x). f(x) = (1/x) [cos(x)  (1/x)sin(x)] + C Differentiate using the product rule, noting that d/dx (1/x) = 1/x^2 gives us f'(x) = (1/x^2) [cos(x)  (1/x)sin(x)] + (1/x) [sin(x)  [(1/x^2)sin(x) + (1/x)cos(x)] ] f'(x) = cos(x)/x^2 + sin(x)/x^3  sin(x)/x + sin(x)/x^2  cos(x)/x And as you can see, it looks nothing like sin(x)/x.
 2 years ago

ahmedelmorsi Group TitleBest ResponseYou've already chosen the best response.0
why we cant solve it by parts ???????????
 2 years ago
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