9. Determine the value of 4r - 1- 4r + 1 lim 10. Determine the value of 11. Determine the value of & to ensure that Ex - 45 26 - 30+3, 122 is continuous everywhere. 12. Show that there exists at least one solution to the equation e" = 2cos(r) on the interval [-2 2). 13. Use first-principles to find the derivative of the function 14. Determine the equation of the tangent line to the curve at the point (1, }). 15. Find the equation of the tangent line to the curve /(z) - sin(x) + cos(s) te" 16. Determine the derivative of the following functions: (a) /(x) = sin(r - 4) (b) /(x) = tan(3r - 1-1) 17. Find the equation of the tangent line to the curve moj = at a = 1. 15. Use logarithmic differentiation to find the derivative of y(a) = (3 + 2)1(r* + 4)