One plus two plus three plus four plus five. How much is 99 plus 100?

One plus two plus three plus four plus five. How much is 99 plus 100?

5050 =（1+100）*50=5050

Given the odd function f (x) defined on R, when x > 0, f (x) = X2, then f (- 1)=______ ．

∵ when x > 0, f (x) = X2, ∵ f (1) = 1, ∵ f (x) is an odd function defined on R, ∵ f (- 1) = - f (1), ∵ f (1) = - 1

It is known that f (x) is an odd function defined on R. when x ≥ 0, f (x) = x & # 178; - X
① Find the analytic expression of F (x), draw the image of F (x), and point out the monotone increasing interval of F (x)

x0
F (x) is an odd function defined on R
f(x)=-f(-x)
=-(x²+x)
=-x²-x
It is also true for x = 0
X≥0
f（x）=X²-X
The monotone increasing interval is
(1 / 2, positive infinity)
It is an odd function
x