\f15. y = 4x -6x2+12x 2x2 16. y = t3 - tz + 4 17. y = 7ex 18. y = -3In (x) 19. Find the slope of the graph of f (x) = 2 + 3 cosx at (n, -1). 20. Find an equation of the tangent line to the graph of y = x4 - 3x2 + 2 at x = 1. 21. If f (x) = 3ex + 4x - 2 then f'(0) = 1 22. If y = - 3 then dy 2 dx VOIAN 2 15 1 5 x-5 b) 2 15 4 5x5 IN 3 C) 5x d) 2x 2x e) 5 5x