Question 873218
Solving for a,
{{{V=(4/3)pi(a^3-b^3)}}}
{{{V=(4/3)pi*a^3-(4/3)pi*b^3}}}
{{{V+(4/3)pi*b^3=(4/3)pi*a^3}}}
{{{a^3=(3V)/(4*pi)+b^3}}}
{{{a=((3V)/(4*pi)+b^3)^(1/3)}}}
Similarly solving for b,
{{{V-(4/3)pi*a^3=(4/3)pi*b^3}}}
{{{b^3=a^3-(3V)/(4*pi)}}}
{{{b=(a^3-(3V)/(4*pi))^(1/3)}}}