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What is the product of the irrational roots of the equation (2x-1)(2x-3)(2x-5)(2x-7)=9?
Read Solution (Total 3)
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- (2x - 1) (2x - 3) (2x - 5) (2x - 7) = 9
let 2x - 4 = p
or (p + 3) (p + 1) (p - 1) (p - 3) = 9
or (p^2 - 1) (p^2 - 9) = 9
or p^4 - 10p^2 + 9 = 9
or p^2 (p^2 - 10) = 0
or p = 0 or ± root 10
2x-4= ± root 10
x= (1/2) [4± root 10]
product of roots = (1/2) [4+ root 10]*(1/2) [4- root 10] = (1/4)*(16-10) =3/2 - 12 years agoHelpfull: Yes(27) No(9)
- Product is 3/2
Expln :
(2x - 1) (2x - 3) (2x - 5) (2x - 7) = 9
Let 2x - 4 = y
=> (y + 3) (y + 1) (y - 1) (y - 3) = 9
=> (y^2 - 1) (y^2 - 9) = 9
=> y^4 - 10y^2 + 9 = 9
=> y^2 (y^2 - 10) = 0
=> y = 0 or ± 8730;(10)
=> 2x - 4 = ± 8730;(10)
=> x = (1/2) [4 ± 8730;(10)]
=> product of the irrational roots
= (1/2)^2 * [4 + 8730;(10)] [4 - 8730;(10)]
= (1/4) * 6
= 3/2. - 12 years agoHelpfull: Yes(10) No(7)
- (2x-1)(2x-3)(2x-5)(2x-7)=9
let 2x-4=y
(y+3)(y-3)(y)
(y^2 - 1) (y^2 - 9) = 9
=> y^4 - 10y^2 + 9 = 9
=> y^2 (y^2 - 10) = 0
=> y = 0 or ± √(10)
=> 2x - 4 = ± √(10)
=> x = (1/2) [4 ± √(10)]
=> product of the irrational roots
= (1/2)^2 * [4 + √(10)] [4 - √(10)]
= (1/4) * 6
= 3/2. - 12 years agoHelpfull: Yes(6) No(4)
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