Mathc initiation/Fichiers c : c77cw2

Sommaire

Application de sin(x)sin(y) ;

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 Etudier:   | sin(ax)sin(bx) dx = 
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                                         | sin(ax)sin(bx) = 1/2 [cos(ax-bx) - cos(ax+bx)] |
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      donc  | sin(ax)sin(bx) dx = | 1/2 [cos(ax-bx) - cos(ax+bx)] dx
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                                = 1/2 |  cos(ax-bx) - 1/2 | cos(ax+bx)  dx                          
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 Exemple:   | sin(3x)sin(2x) dx = = 1/2 |  cos(3x-2x) - 1/2 | cos(3x+2x)  dx
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                                  = 1/2 |  cos(x) - 1/2 | cos(5x)  dx    
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