通过乘以,
#H(X)=(X-SQRT {X})(X + SQRT {X})= X ^ 2-X#
通过权力规则,
#H'(X)= 2X-1#.
我希望这有用。
如果你注意到了 #H(x)的# 是完美正方形的差异然后问题更容易。
如果你不这样做,你可以使用 产品规则.
#H '(X)= UV' + VU'#
#H(X)= UV =(X-SQRT(X))(X + SQRT(X))=(X-X ^(1/2))(X + X ^(1/2))#
#H'(X)=(X-X ^(1/2))(1 + 1/2×^( - 1/2))+(X + X ^(1/2))(1-1 / 2×^( -1/2))#
#H'(X)=(X-X ^(1/2))(1 + 1 /(2×^(1/2)))+(X + X ^(1/2))(1-1 /(2× ^(1/2)))#
#H'(X)= X + X /(2×^(1/2)) - X ^(1/2)-x ^(1/2)/(2×^(1/2))+ XX /( 2X ^(1/2))+ X ^(1/2)-x ^(1/2)/(2×^(1/2))#
#H'(X)= X + X /(2×^(1/2)) - X ^(1/2)-1 / 2 + XX /(2×^(1/2))+ X ^(1 / 2)-1 / 2#
#H'(X)= X + X /(2×^(1/2)) - X ^(1/2)+ XX /(2×^(1/2))+ X ^(1/2)-1- #
#H'(X)= X + X /(2×^(1/2))+ X-X /(2×^(1/2)) - 1#
#H'(X)= X + X-1#
#H'(X)= 2X-1#