If the gradient of the curve y = 2kx2 + x + 1 at x = 1 is 9, find k.
4
3
2
1
Correct answer is C
y = 2kx2 + x + 1
Gradient function dy/dx = 4kx + 1
at dy/dx = 9, => 9 = 4kx + 1
=> 8 = 4kx, and k = 8/4x.
At x = 1, k = 8/4 = 2
The chord ST of a circle is equal to the radius, r, of the circle. Find the length of arc ST.
πr/6
πr/2
πr/12
πr/3
Correct answer is D
Since ST = the radius r, => SOT is equilateral.
Each angle = 60°
Length of arc ST = θ/360 x 2πr
= 60/360 x 2 x π x r = πr/3
Find the locus of a point which moves such that its distance from the line y = 4 is a constant, k.
y = 4 \(\pm\) k
y = k \(\pm\) 4
y = 4 + k
y = k - 4
Correct answer is A
No explanation has been provided for this answer.
23 m
25 m
20 m
22 m
Correct answer is C
Capacity = Volume = 3080m3
base diameter = 14m
radius = \(\frac{\text{diameter}}{2}\)
= 7m
Volume of Cylidner = Capacity of cylinder
πr2h = 3080
\(\frac{22}{7}\) × 7 × 7 × h = 3080
h = \(\frac{3080}{22 \times 7}\)
h = 20m
040°
070°
280°
320°
Correct answer is B
Hint: Simply make a sketch of the question and find the bearing to be 070°