Page 38 - CHAPTER 4 (Quadratic equations)
P. 38
CHAPTER 4
QUADRATIC EQUATIONS
(iii) If D>0 then the sign of the quadratic expression ax +bx+c, is
2
determined as follows:
D>0
F. Equations Reducible to Quadratic Equation:
TYPE-I ax + bx + c = 0
2n
n
2
n 2
n
Method: In this type of equations, we put x = y, so that y = (x ) = x
2n
and the given equation becomes ay + by +c = 0, which is a quadratic
2
equation.
1
1
2
TYPE-2 a(x ± ) ±b (x± )+c=0 , a, b ,c are constants.
x 2 x
1
Method: Put (x± )=y then the given equation reduces to a(y 2±2)±by+c=0.
x
TYPE-3 Equation of the form am + bm + c = 0
2x
x
Method: Put m = y, then the given equation becomes
x
ay + by + c = 0.
2
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