Exercise 6.5

Choose the correct answer The point on the curve x^ 2 = 2y which is nearest to the point (0, 5) is (A) (2 2,4) (B) (2 2,0) (C) (0, 0) (D) (2, 2)

Equation of the curve is                                                                                 ……….(i) Let P be any point on the curve (i), then according to question, Distance between...

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A wire of length 28 m is to be cut into two pieces. One of the pieces is to be made into a square and the other into a circle. What should be the length of the two pieces so that the combined area of the square and the circle is minimum?

 Let  meters be the side of square and  meters be the radius of the circle. Length of the wire = Perimeter of square + Circumference of circle    = 28      ……….(i) Area of square =  and Area of...

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A rectangular sheet of tin 45 cm by 24 cm is to be made into a box without top, by cutting off square from each corner and folding up the flaps. What should be the side of the square to be cut off so that the volume of the box is maximum ?

Dimensions of rectangular sheet are 45 cm and 24 cm. Let  cm be the side of each of the four squares cut off from each corner. Then dimensions of the open box formed by folding the flaps after...

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A square piece of tin of side 18 cm is to be made into a box without top, by cutting a square from each corner and folding up the flaps to form the box. What should be the side of the square to be cut off so that the volume of the box is the maximum possible.

Each side of square piece of tin is 18 cm. Let  cm be the side of each of the four squares cut off from each corner. Then dimensions of the open box formed by folding the flaps after cutting off...

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Find the absolute maximum value and the absolute minimum value of the following functions in the given intervals: (i) f(x) = x^ 3 , x ∈ [– 2, 2] (ii) f (x) = sin x + cos x , x ∈ [0, π]

 (i) Given:     Now      At   At   At   Therefore, absolute minimum value of  is  and absolute maximum value is 8. (ii) Given:     Now          [Positive]   is in I quadrant. [ ]       Therefore,...

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Find the local maxima and local minima, if any, of the following functions. Find also the local maximum and the local minimum values, as the case may be:(vii) g(x)=1/(x^2+2) (viii) f (x )=x√1- x , 0 <x<1

(vii) Given:       and =  Now      [Turning point] At    [Negative]    is a point of local maxima and local maximum value is  (viii) Given:      =  =  =  And  =  =  Now    = 0        is a point of...

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Find the local maxima and local minima, if any, of the following functions. Find also the local maximum and the local minimum values, as the case may be:(v) f(x) = x ^3 – 6x^ 2 + 9x + 15 (vi) x/2+2 /x , x>0

(v) Given:       and  Now          or    [Turning points] At   [Negative]    is a point of local maxima and local maximum value is  At     [Positive]    is a point of local minima and local minimum...

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Find the local maxima and local minima, if any, of the following functions. Find also the local maximum and the local minimum values, as the case may be: (iii) h(x) = sin x + cos x, 0 2 x π < < (iv) f(x) = sin x – cos x, 0 2 < < π

(iii) Given:         ……….(i)     and  Now            [Positive]    can have values in both I and III quadrant. But,  therefore,  is only in I quadrant.   =  [Turning point] At     = ...

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Find the local maxima and local minima, if any, of the following functions. Find also the local maximum and the local minimum values, as the case may be: (i) f(x) = x ^2 (ii) g(x) = x^ 3 – 3x

(i) Given:       and  Now        [Turning point] Again, when ,    [Positive] Therefore,  is a point of local minima and local minimum value =  (ii) Given:       and  Now           or  [Turning...

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