If the harmonic mean between roots of `(5+sqrt(2))x^2-b x+8+2sqrt(5)=0i s4` , then find the value of `bdot`

If the harmonic mean between the roots of (5+sqrt(2))x^(2)-bx+(8+2sqrt(5))=0 is 4 then the value of b is

For sqrt(2) x^2 - 5x + sqrt(2) = 0 find the values of the discriminant .

If the difference between the roots of the equation x^(2)+ax+1=0 is less then sqrt(5) , then find the set of possible value of a .

Find the roots of the equation sqrt(2)x^(2)+7x+5sqrt(2)=0

Find the harmonic mean of the roots of the equation (5+sqrt(2))x^(2)-(4+sqrt(5))x+(8+2sqrt(5))=0