Question

if a and b are roots of 8x^2-99x+72=0, then a+b/a^-1+b^-1 is​

Answer 1

Explanation:

we find a+b(a^-1 +b^-1)

=a+b/(1/a +1/b)

=a+b(a+b/ab)=ab

wkt general form of quartic eqn

x^2-(sum of roots )x+product of roots

equate to given question

x^2-99x/8+72/8

product of roots =72/8=9

product of roots =ab=9