Let k 2-2k-1= 0 and get k = 1 √ 2. Because the previous coefficients may affect the positive and negative of the function, it is necessary to find the dividing point of the positive and negative coefficients. Let k 2+k=0 and get k=0 or-1. Discuss according to the situation.
When 1. K = 1 √ 2, the exponent is 0 and the function becomes y = k 2+k, and the change of x does not affect the function value.
2. When k =- 1 or 0, y=0, and the function value remains unchanged.
3. when k
4.- 1 & lt; When k< 1-√2, the coefficient is negative, the exponent is positive, and the power function decreases, so the function value decreases with the increase of x.
5. 1-√2 & lt; K<0, the coefficient is negative, the exponent is negative, and the power function is increasing, so the function value increases with the increase of X.
6.0<k< 1+√2, the coefficient is positive, the exponent is negative, and the power function decreases, so the function value decreases with the increase of x.
7. When k>1+√ 2, the coefficient and exponent are positive, and the power function increases, so the function value increases with the increase of x.
Just write out the final comprehensive conclusion.