1.

If `x^({(3)/(4)("log"_(3)x)^(2) + ("log"_(3)x)-(5)/(4)}) = sqrt(3)`, then x hasA. all integral valuesB. two integral values and one irrational valuesC. all irrational valuesD. two rational values and an irrational value

Answer» Correct Answer - D
We have,
`x^({(3)/(4)("log"_(3)x)^(2) + ("log"_(3)x)-(5)/(4)}) = sqrt(3)`
`rArr (3)/(4) ("log"_(3) x)^(2) + ("log"_(3) x)- (5)/(4) = "log"_(x) sqrt(3)`
`rArr (3)/(4) ("log"_(3)x)^(2) + "log"_(3) x - (5)/(4) = (1)/(2"log"_(3)x)`
`rArr (3)/(2) ("log"_(3)x)^(3) + 2("log"_(3)x)^(2)- (5)/(2)("log"_(3)x)-1 = 0`
`rArr 3("log"_(3)x)^(3) + 4("log"_(3)x)^(2) -5("log"_(3)x) -2 =0`
`rArr ("log"_(3)x-1)(3"log"_(3)x+1)("log"_(3)x+2) =0`
`rArr "log"_(3)x =1, -(1)/(3), -2 rArr x = 3, 3^(-1//3), 3^(-2)`
Clearly, x takes two rational values and an irrational value.


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