Qualification > Math
Pure math(p3)
twilight:
--- Quote from: preity on May 28, 2009, 08:56:23 am ---Can someone help me with this questions
M/J 02 Q1
M/J 03 Q1
0/N 04 Q4
--- End quote ---
for m/j 2003 Q1(i)
sin(x-60) - cos(30-x) = 1
use the formula sheet here
sin x cos 60 - sin 60 cos x - ( cos 30 cos x + sin 30 sin x ) = 1
sin x cos 60 - sin 60 cos x - cos 30 cos x - sin 30 sin x = 1
(1/2)sin x - (3/2)cos x - (3/2)cos x - (1/2)sin x = 1
(-3)cos x = 1
cos x = -1/3
twilight:
--- Quote from: preity on May 28, 2009, 08:56:23 am ---Can someone help me with this questions
M/J 02 Q1
M/J 03 Q1
0/N 04 Q4
--- End quote ---
m/j 2003 Q1(ii)
cos x = -1/3
reference angle = cos-1 (1/3) = 54.7o
therefore x = 180 + 54.7 = 125.3o
candy:
The polynomial x^4 - 2x^3 - 2x^2 +a is denoted by f(x). It is given that f(x) is divisible by x^2 - 4x +4.
(i) Find the value of a.
(ii) When a has this value, show that f(x) is never negative.
can someone please explain part (ii)
i don't understand the question :(
astarmathsandphysics:
--- Quote from: candy on May 28, 2009, 01:02:36 pm ---The polynomial x4 ?2x3 ?2x2 +a is denoted by f(x). It is given that f(x) is divisible by x2 ?4x +4.
(i) Find the value of a.
(ii) When a has this value, show that f(x) is never negative.
can someone please explain part (ii)
i don't understand the question :(
--- End quote ---
can you modify this post? the question is not clear
ITS MEE...:
can someone solve the last part please
An underground storage tank is being filled with liquid as shown in the diagram. Initially the tank is
empty. At time t hours after filling begins, the volume of liquid is V m3 and the depth of liquid is h m.
It is given that V = 4
3h3.
The liquid is poured in at a rate of 20m3 per hour, but owing to leakage, liquid is lost at a rate
proportional to h2. When h = 1,
dh
dt = 4.95.
(i) Show that h satisfies the differential equation
dh
dt = 5
h2 ? 1
20
. [4]
(ii) Verify that
20h2
100 ?h2 ? ?20 + 2000
(10 ?h)(10 +h). [1]
(iii) Hence solve the differential equation in part (i), obtaining an expression for t in terms of h.
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