Find the intervals in which the function f given by  f (x) = 2x2 – 3x is
(a)
increasing
(b)
decreasing
5 Find the intervals in which the function f given by f(x) = 2x3 – 3x2 – 36x + 7 is
(a)
increasing
(b)
decreasing
6 Find the intervals in which the following functions are strictly increasing or
decreasing:
(a)
x2 + 2x – 5
(b)
10 – 6x – 2x2
(c)
–2x3 – 9x2 – 12x + 1
(d)
6 – 9x – x2
(e)
(x + 1)3 (x – 3)3
7 Show that 
2
log(1
)
2
x
y
x
x
=
+
−
+
, x > – 1, is  an increasing function of x
throughout its domain