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A running track of 440 ft . is to be laid out enclosing a football field, the shape of which is a rectangle with a semi-circle at each end. If the area of the rectangular portion is to be maximum then the lengths of its sides are -

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Important Questions on Application of Derivatives

MEDIUM
If x=-1 and x=2 are extreme points of fx=αlogx+βx2+x, then 
HARD
If z is a non-real complex number, then the minimum value of Im z5Im z5 is (Where Im z = Imaginary part of z)
HARD
Let k and K be the minimum and the maximum values of the function fx=1+x0.61+x0.6 in 0, 1, respectively, then the ordered pair (k, K) is equal to:
EASY
Let M and m be respectively the absolute maximum and the absolute minimum values of the function, fx=2x3-9x2+12x+5 in the interval [0,3] . Then M-m is equal to
MEDIUM
The least value of αR for which, 4αx2+1x 1, for all x>0, is 
HARD
The maximum value of fx=logxx (x0,x1) is
MEDIUM
From the top of a 64 metres high tower, a stone is thrown upwards vertically with the velocity of 48 m/s. The greatest height (in metres) attained by the stone, assuming the value of the gravitational acceleration g=32 m/s2, is:
HARD
Let fx=x2+1x2 and gx=x-1x, xR--1, 0, 1. If hx=fxgx , then the local minimum value of hx is:
 
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The maximum area (in sq. units) of a rectangle having its base on the x- axis and its other two vertices on the parabola, y=12-x2 such that the rectangle lies inside the parabola, is :
HARD
If the function f given by fx=x3-3a-2x2+3ax+7, for some aR is increasing in 0, 1 and decreasing in 1, 5, then a root of the equation, fx-14x-12=0, x1 is :
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A rectangular sheet of fixed perimeter with sides having their lengths in the ratio 8:15 is converted into an open rectangular box by folding after removing squares of equal area from all four corners. If the total area of removed squares is 100, the resulting box has maximum volume. Then the lengths of the sides of the rectangular sheet are:

MEDIUM

A rope of length 40 metres is cut into two pieces and two squares are made on the floor with them. The sum of the areas enclosed is 58 square metre.

What are the lengths of the sides of the squares ?

HARD
The function fx=2x+x+2-x+2-2x has a local minimum or a local maximum at x=
MEDIUM
Twenty meters of wire is available for fencing off a flower-bed in the form of a circular sector. Then the maximum area (in sq. m) of the flower-bed, is:
MEDIUM
If non-zero real numbers b and c are such that  min fx>max gx, where fx=x2+2bx+2c2 and gx=-x2-2cx+b2, xR; then cb lies in the interval 
MEDIUM
A wire of length 2 units is cut into two parts which are bent respectively to form a square of side =x units and a circle of radius =r units. If the sum of the areas of the square and the circle so formed is minimum, then
HARD
For every pair of continuous functions f, g :0, 1R such that maxfx: x0, 1=max{gx: x0, 1}, then the correct statement(s) is(are)
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The maximum value of fx=x4+x+x2 on [-1, 1] is
HARD
Let f :R0,  and g :RR be twice differentiable functions such that f  and g  are continuous functions on R . Suppose f ( 2 )=g( 2 )=0,  f ( 2 )0 and g'(2)0limx2f(x) g(x)f' (x) g'(x)=1, then
EASY

The perimeter of the base of a square pyramid is 96 cm and its height is 16 cm. What is the length of a base edge?