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1. Determine the equation of the tangent to y xcos2x at x=It/2 [4 ] 2. Find the derivatives of the following: [EACH 3] a) y = cos?(tx) , tER b) y = ecsex c) y = x'secx 3. If the function y = nx- - mx + 25 takes on the value of 20 when x = 5, and the rate of change is -7 at that point, what are m and n? [7] 4. You are given the function f (x) = x* + x2 -5. Find the critical point(s). [5] 5. Find the absolute extrema (maximum or minimum) points. [5] y = xe *, for x E [-1,2]