Math question: Prove that if two angles and the included side of one triangle are congruent to two angles and the included side of another triangle, then the triangles are congruent.
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What are the rectangular coordinates of a unit vector pointing in the direction of (3, -4)?
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Chain rule variants state that if u(x) and v(x) are differentiable functions of x, then the derivative of u(v(x)) is given by u'(v(x)) * v'(x). Question: Find the derivative of f(x) = sin(2x^2 + 3x - 1) using the chain rule.