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If A.M. and G.M. of roots of a quadratic equation are 8 and 5, respectively, then obtain the quadratic equation. - Mathematics

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प्रश्न

If A.M. and G.M. of roots of a quadratic equation are 8 and 5, respectively, then obtain the quadratic equation.

योग

उत्तर

Let the root of the quadratic equation be a and b.

According to the given condition,

A.M. = `(a + b)/2 = 8 = a + b = 16`    ...(1)

G.M. = `sqrt(ab) = 5 = ab = 25`    ...(1)

The quadratic equation is given by,

x2– x (Sum of roots) + (Product of roots) = 0

x2 – x (a + b) + (ab) = 0

x2 – 16x + 25 = 0 [Using (1) and (2)]

Thus, the required quadratic equation is x2 – 16x + 25 = 0

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अध्याय 9: Sequences and Series - Exercise 9.3 [पृष्ठ १९३]

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एनसीईआरटी Mathematics [English] Class 11
अध्याय 9 Sequences and Series
Exercise 9.3 | Q 32 | पृष्ठ १९३

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