Question

find a quadratic polynomial whose zeroes are -2/√3 and √3/4

Answer 1

here, α=-2/√3
       β=√3/4
every quadratic polynomial has this relation with their zeros
k[x²-(α+β)x+αβ]  (this formula was is chapter 2 polynomial tenth ncert book in an example

putting values
k[x²+5/4√3x-2√3/4√3]
 k[x²+5/4√3x-1/2]
 here k=4√3 because this is only in denominator
=4√3x²+5x-2√3         is the required quadratic polynomial
                                                                                                                                                                                                             

Answer 2

4√3x² + 5x - 2√3 is the correct answer.