Question 1 What is the sum of the irrational roots of the equation (x-1)(x-3)(x-5)(x-7)=9 ? a)10 b)8 c)6 d)4 Answer : b)8 Solution: Given that (x - 1) (x - 3) (x - 5) (x - 7) = 9 Let x - 4 = p Then the given eqn becomes (p + 3) (p + 1) (p - 1) (p - 3) = 9 (p 2 - 1) (p 2 - 9) = 9 p 4 - 10p 2 + 9 = 9 p 2 (p 2 - 10) = 0 p 2 =0 or p 2 -10 =0 p = 0 or p = sqrt(10) or p = - sqrt(10) then x - 4 = 0, x - 4 = sqrt(10) or x - 4 = - sqrt(10) Now the roots of the given eqn are 4,4 + sqrt(10) and 4 - sqrt(10) The irrational roots are 4+sqrt(10) and 4 - sqrt(10) The sum of the irrational roots = 4 + sqrt(10) + 4 - sqrt(10) = 8. Hence the answer is 8. Question 2 The product of the distinct roots of the equation (3x)(3x+2)(3x-4)(3x-6)= 64 is: a)-32/27 b)-61/5 c)63/16 d)69/12 Answer : a)-32/27 Solution: Given that (3x)(3x+2)(3x-4)(3x-6)= 64 Let 3x - 2 = p Then the given eqn becomes (p + 2) (p + 4) (p - 2) (p - 4) = 64 (p 2 - 4) (p 2 - 16...
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