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Question
Find a cubic polynomial whose zeroes are 2, -3and 4.
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Solution
If the zeroes of the cubic polynomial are a, b and c then the cubic polynomial can be found as
`x^3 – (a + b + c)x^2 + (ab + bc + ca)x – abc` .................(1)
Let a = 2, b = –3 and c = 4
`x^3 – (2 – 3 + 4)x^2 + (– 6 – 12 + 8)x – (–24)`
`⇒ x^3 – 3x^2 – 10x + 24`
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Case Study -1

The figure given alongside shows the path of a diver, when she takes a jump from the diving board. Clearly it is a parabola.
Annie was standing on a diving board, 48 feet above the water level. She took a dive into the pool. Her height (in feet) above the water level at any time ‘t’ in seconds is given by the polynomial h(t) such that h(t) = -16t2 + 8t + k.
The zeroes of the polynomial r(t) = -12t2 + (k - 3)t + 48 are negative of each other. Then k is ______.
The below picture are few natural examples of parabolic shape which is represented by a quadratic polynomial. A parabolic arch is an arch in the shape of a parabola. In structures, their curve represents an efficient method of load, and so can be found in bridges and in architecture in a variety of forms.




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