Question 881846
{{{f(x,y) = x^4 + 3x^2y^2 + y^4 }}}
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{{{f(ax,ay) = (ax)^4 + 3(ax)^2(ay)^2 + (ay)^4 }}} 
{{{f(ax,ay) = a^4x^4 + 3a^4x^2y^2 + a^4y^4 }}}
{{{f(ax,ay) = a^4(x^4 + 3x^2y^2 + y^4) }}}
{{{f(ax,ay) = a^4*f(x,y) }}}