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3 years ago

11

dado los vectores a=3.5 b=4 c=6.5 , si se sabe que a+b+c=0 (resultante) cual es el angulo formado por A y B?

1 answer:

lawyer [7]3 years ago

6 0

cos(A) = (b2 + c2 − a2) / 2bc = (16+6.5^2-3.5^2)/(2*4*6.5) = 0.88461538 so A = cos−1 (0.88461538) = 27.79 Deg cos(B) = (c2 + a2 − b2)/2ca = (3.5^2+6.5^2-16)/(2*3.5*6.5) = 0.84615385 so B = cos−1 (0.84615385) = 32.2 Deg

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