(3m+3k)-(mk+k²)=3(m+k)-k(m+k)=(m+k)(3-k)
2p- 14p²/7p+3= 14p²+6p-14p²/7p+3=6p/7p+3
2b²-b/b³+1-b-1/b²-b+1= b(2b-1)/(b+1)(b²-b+1)-b-1/b²-b+1=b(2b-1)-b²+1/(b+1)(b²-b+1)=2b²-b-b²+1/(b+1)(b²-b+1)=b²-b+1/(b-1)(b²-b+1)=1/b+1
см.рис
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