一道初中数学题(1)/(a-x)-(1)/(a+x)-(2x)/(a²+x²)-(4x³)/(a^4+x^4)+(8x^7)/(x^8-a^8)
2019-06-02
一道初中数学题
(1)/(a-x)-(1)/(a+x)-(2x)/(a²+x²)-(4x³)/(a^4+x^4)+(8x^7)/(x^8-a^8)
优质解答
1/(a-x)-1/(a+x)-2x/(a²+x²)-4x³/(a⁴+x⁴)+8x⁷/(x⁸-a⁸)
=2x/(a²-x²)-2x/(a²+x²)-4x³/(a⁴+x⁴)+8x⁷/(x⁸-a⁸)
=4x³/(a⁴-x⁴)-4x³/(a⁴+x⁴) + 8x⁷/(x⁸-a⁸)
=8x⁷/(a⁸-x⁸)+ 8x⁷/(x⁸-a⁸)
=8x⁷/(a⁸-x⁸)- 8x⁷/(a⁸-x⁸)
=0
1/(a-x)-1/(a+x)-2x/(a²+x²)-4x³/(a⁴+x⁴)+8x⁷/(x⁸-a⁸)
=2x/(a²-x²)-2x/(a²+x²)-4x³/(a⁴+x⁴)+8x⁷/(x⁸-a⁸)
=4x³/(a⁴-x⁴)-4x³/(a⁴+x⁴) + 8x⁷/(x⁸-a⁸)
=8x⁷/(a⁸-x⁸)+ 8x⁷/(x⁸-a⁸)
=8x⁷/(a⁸-x⁸)- 8x⁷/(a⁸-x⁸)
=0