The curve, C has equation y = 2x^2 +5x +k. The minimum value of C is -3/4. Find the value of k.
Notes: At the minimum point of the curve, the gradient is = 0. You can find the gradient of a curve by taking the derivative of a point in the curve. We also know that when the curve is at a minimum, y =-3/4.With this is mind, you can solve the question by taking these steps:Step 1 : Differentiate the equation of the curve get 4x+5 , Step 2: To find where the curve is at a minimum, set the dy/dx = 0. so 4x+5=0 therefore, we find x= -5/4.Step 3: We know At the minimum points, x= -5/4 and y=-34 so we can substitute these into the equation of the curve to find the unknown variable k. k = 19/8
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