If m is positive but not greater than 3 then show that the roots of the equation (m-2)x2 - (8-2m)x - (8-3m) = 0 are real . find the range of values of m for which one root is positive and the other root is negative

Dear Student,

(m-2) x2 - (8-2m)x - (8-3m) = 0

Comparing it with ax2 +bx +c = 0

a = (m-2) , b = -(8-2m) , c = -(8-3m)

D = b2 - 4ac
For roots to be real D must be greater than equal to 0.
Therefore,

D = (8-2m)- 4(m-2) (-(8-3m))
   = 64 - 32m + 4m2 + 4 (8m - 3m2 - 16 + 6m​2 
  = 4 (16 - 8m + m+ 8m + 3m- 16)
 = 4 (4m2 
= 16 m2  
Hence, D is grater than 0 and the roots are real 

Now, one root is positive and other negative
Hence, product of roots is less than 0

Product of roots = ca = -(8-3m)(m-2) < 0
(3m-8)(m-2) <0

2<m<83

Regards

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