Х+7_х^2-25 - 2х+2_х^2-25 при х=-5,1

X+7/x²-25-2x+2/x²-25
x+7-2x(x²-25)+2/x²-25
x+7-2x³+50x+2/x²-25
-2x³+51x+9/x²-25
-2*(-5.1)³+51*(-5.1)+9/(-5.1)²-25
-2*(-5.1)³-206,1+9/(-51/10)²-25
2*(51/10)³-2601/10+9/51²/100-25
2*51³/10³-2601/10+9/51²-2500/100
2*51³/5³*2³-2601/10+900/51²-2500
51³/5³*2²-2601/10+900/2601-2500
51³/125*4-2601/10+900/101
51³/500-2601/10+900/101
51³/500-253701/1010
≈14.11