If r = [−3, 1] × [0, 2], use a riemann sum with m = 4, n = 2 to estimate the value of (y2 − 2x2) da. r take the sample points to be the upper left corners of the squares.

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Cot(90° − x) = 1 the value of x that satisfies this equation is °. a. 60 b. 135 c. 225 d. 315

Rhombus adef is inscribed into a triangle abc so that they share angle a and the vertex e lies on the side bc . what is the length of the side of the rhombus if ab=c, and ac=b.