Turunan kedua dari y = x^2/x+1 adalah

y = x²/x + 1
y = u/v
y' = u'v - uv'/v²
mis u = x²
u'= 2x
v= x + 1
v'= 1

y' = u'v - uv' / v²
y' = 2x ( x + 1) - x² (1)/ v²
y'= 2x² + 2x - x²/ (x+1)²
y' = x² + 2x/ (x+1)²
y' = x² + 2x/ x² + 2x + 1

y" = x² + 2x/ x² + 2x + 1
u = x² + 2x
u'= 2x + 2
v= x² + 2x + 1
v' = 2x + 2
y" = u'v - uv'/ v²
y" = 2x + 2 ( x² + 2x + 1) - x² + 2x (2x + 2)/ (x² + 2x +1)²
y"= 2x³ + 4x² + 2x + 2x² + 4x + 2 - 2x³ - 2x + 4x² + 4x / (x² + 2x + 1)²
y" = 10x² + 8x + 2/ (x² + 2x + 1)²

semoga membantu