Recent content by Andrewlorenzo

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    Proof of Cosine law using vectors

    Homework Statement Two vectors of lengths a and b make an angle θ with each other when placed tail to tail. Prove, by taking components along two perpendicular axes, that the length of the resultant vector is r=√(a^2+b^2+2abcos θ ) Homework Equations Would this be correct? How would you...