Bài tập CALCULUS 48

Created by T Madas Question 173 (****) y=3x+ 27 , x ≠ x Find the range of values of x for which y is increasing MP1-D , x > 27 Created by T Madas Created by T Madas Question 174 (****) The points ( −2, −1) and (1, −4 ) lie on the curve C with equation y = f ( x ) The gradient function of C is given by dy = 3x + x + k , dx where k is a constant a) Find an equation of C , in the form y = f ( x ) The straight line L has equation y = −3 x − b) Show that L is a tangent to C and determine further the coordinates of the point of tangency C1O , y = x3 + x − x − , Created by T Madas ( −1, −2 ) Created by T Madas Question 175 (****) y O C x L2 L1 L3 The figure above shows the curve C with equation x4 − x + , x ≠ y= 6x The straight line L1 has equation y = 15 x The straight lines L2 and L3 are tangents to C Given that L1 , L2 and L3 are parallel to one another, determine an equation of L2 and an equation of L3 C1V , y = 15 x − 18 or y = 15 x − , 12 y = 45 x + 50 or y = 15 x + 25 4 Created by T Madas