VIRTUAL COACHING CLASSESORGANISED BY BOS (ACADEMIC), ICAI

FOUNDATION LEVEL PAPER 3:BUSINESS MATHEMATICS LOGICAL REASONING

AND STATISTICS

Faculty: CA RASHMI LONIKAR

© The Institute of Chartered Accountants of India

Date: 22nd July, 2021

QUADRATIC EQUATIONS▪ Form of equation : ax 2 + bx + c = 0

▪Roots of the equation are two

𝐱 =−𝐛 − 𝐛 𝟐 − 𝟒 𝐚𝐜

𝟐𝐚

And

𝐱 =−𝐛 + 𝐛 𝟐 − 𝟒 𝐚𝐜

𝟐𝐚21 July 2021

© THE INSTITUTE OF CHARTERED ACCOUNTANTS OF

INDIA2

▪1) x 2 -5x + 6 = 02) x 2 - x - 6 = 03) x 2 -2x – 8 = 04) 6x 2 +5x -6 = 05) x 2 -2x -15 = 0

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NATURE OF ROOTS

▪Ans

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▪Ans:

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Pg 2.16 Examine roots of equation

▪1) x 2 -8x +16 = 0

▪2) 3x 2 -8x + 4 = 0

▪3) 5x 2 -4x -2 = 0

▪4) 2x 2 -6x -3 = 0

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▪Sum of roots

Product of roots

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FORMATION OF QUADRATIC EQUATION

▪When sum of roots and product of roots is given, we can form the quadratic equation by

▪ x 2 - (sum of roots) x + (product of roots) = 0

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Pg 2.17

▪ How to form new eqn?

▪Step 1 Find the roots

▪Step 2 : Substitute in expression

▪Step 3: Construct/ form new eqn

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Ex F

▪Ans:

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WORD PROBLEMS –QUADRATIC pg 2.25 Ex H

▪Ans: c, b, a

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▪Ans: a, a, c

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