309X2+1
x2-5x+1=0则x2+x2/1
(X2 -y+1)(X2+1)+X2y+y -X2因式分解
X2/X1(X1+X2)+X3/(X1+X2)(X1+X2+X3)+.Xn/(x1+x2+...Xn-1)(X1+X2.
求arctanx/(x2(1+x2))的不定积分?
lim(根号X2+X-根号X2+1)
解方程:X2--1/8(X2+2X)+X2+2X/3(X2--1)=11
(巧解题) 已知x2+3x2+1=0 ,求x2+1/x2 的值?
(x2+1)2-4x(x2-1)因式分解
f(X)=1-x2/1+x2的值域
y=x2-1/x2+1 求值域
2( x2 +1/x2) - 9( x + 1/x) + 14 =
证明:根号(x2+2x+4)-根号(x2-x+1)