Question 1:
a) If possible, find the inverse of the function defined by y = x+2/ 2x-1
b) Do the following define one-to-one functions? Is it one-to-one or not?
i) y = cos x
ii) y = 3 -x2
iii) y = |x|
iv) y = sinhx
c) Functions f and g are defined by f (x) = x-2/5, g(x) = 5x +2,
i) Calculate f(g(x)).
ii) Calculate g(f(x)).
iii) Are f and g an inverse pair? Explain your answer.
d) Simplify cos(sin-1 x).
e) Simplify ln(7x + 2) + ln(1/(7x+2)). What are the restrictions on x?
f) Use the definition of the hyperbolic sine function to evaluate sinh(0.76) , giving you answer correct to 2 decimal places.
g) Express cosh-1 3 in terms of natural logarithms.
h) If possible, solve ln(x - 7) = ln(7 - x) where x is a real number.
i) Assume that f is a one-to-one function.
i) If f(2) = 6, what is f-1 (6)?
ii) Evaluate f-1 ( f (Π)).
iii) If b is real and f-1 (b) = 3 , what is f (b)?
Question 2:
a) Use the definitions of cosh x and sinh x in terms of exponential functions to evaluate sinh x -cosh x.
b) Prove that tanh-1 x = 1 ln(1+x/1-x).
c) Prove the change of base formula logbx = logax/logab.
Question 3:
a) If h(x) = 4x + 2ln x, then what does h-1 (4) equal?
b) The graphs of f and g are given. If possible, evaluate:
i) g( f (1)) =
ii) f (g(1)) =
iii) f-1(-1) =
c) If possible, solve logm (logm x) = 1
Question 4:
a) Consider the complex number z = 5 + 12i . Evaluate:
i) Re(z)
ii) Im(z)
iii) |z|
iv) Arg (z) .
b) Express z = 1 + i√3 in polar form.
c) Evaluate e3iΠ .
d) Solve z2 = - i where z is a complex number. Express your answers in rectangular (or Cartesian) form.
e) Let
4x -5, x ≤ 4
f(x) = 3, x> 4
Evaluate
i) lim f(x)
x → 4-
ii) lim f(x)
x → 4+
iii) lim f(x)
x → 4
f (x)
f (x)
f (x).
f) Evaluate
i)
limx → 2 ((3 - 2x)/ (3 + 2x))
ii) lim (4 - x2)/(x - 2)
x → 2
g) Evaluate
i)
lim (x/(x-2))
x → 2-
ii)
lim ( x/x-2)
x → 2+
iii)
lim ( x/x-2 )
x → 2
h) Evaluate
lim (√x2 +1)/(2x+3)
x → - ∞
i) Evaluate
lim (√(x2 + x+ 1) -1)
x → ∞
Question 5:
a) Find the horizontal asymptote(s) of f(x) = e-x/2ex + e-x.
b) A function y = f (x) is said to be continuous at x = c , if ALL three of the following statements are true:
i) f (c) exists
ii) lim f(x) exists
x → c
iii) lim f(x) = f(c).
x → c
Which conditions in the definition of continuity are not satisfied at x=1 following function?
x2 -1/x-1 x ≠ 1
f (x) =
2, x = 1
c) Let z = c + id be a complex number, where c and d are real numbers. Prove that the product of z and its conjugate is a real number.
Question 6:
a) Evaluate the expression ii , where i = √-1, in the form a + ib and a and b are realnumbers
b) If possible, find all values of a that will make the following function continuous:
2x + 5 x < 1
f (x) =
3a, x > 1
c) Explain the meaning of the mathematical concept "limit".