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The equation `x^((3/4)(log_2 x)^2 + (log_2 x) - (5/4))=sqrt(2)`has`(1)`at least one real solution`(2)`exactly three solutions`(3)`exactly one irrational solution`(4)`complex roots

Answer» `x^((3/4)(log_2x)^2 +log_2x - 5/4) = sqrt2`
Taking logs both sides,
`=>((3/4)(log_2x)^2 +log_2x - 5/4)log_2 x = log_2 2^(1/2)`
`=>((3/4)(log_2x)^2 +log_2x - 5/4)log_2 x = 1/2`
Let `log_2x = t`
Then, equation becomes,
`=>(3/4t^2+t-5/4)t = 1/2`
`=>3t^3+4t^2-5t-2 = 0`
`=>(t-1)(3t^2+7t+2) = 0`
`=>(t-1)(3t^2+6t+t+2) = 0`
`=>(t-1)(t+2)(3t+1) = 0`
`=>t = 1 or t = -2 or t = -1/3`
`=>log_2x = 1 or log_2x = -2 or log_2x = -1/3`
`=>x = 2^1,2^(-1/3) , 2^(-2)`
So, there are exactly three solutions for `x`.


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