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Объяснение:
1) y'=((7x²+3x-1)¹/³)'=(1/3)*(7x²+3x-1)⁻²/³)*(14x+3)=(14x+3)/∛(7x²+3x-1)²
2) y'=5*(3x²-7)+6x*(5x+1)=15x²-35+30x²+6x=45x²-35+6x
3) y'=(5*(7x²+1)-14x*(5x+3))/(7x²+1)²=(35x²+5-70x²-42x)/(7x²+1)²=
(-35x²+5-42x)/(7x²+1)²
