题干

巴山市某重点中学“发现数学的美丽”尖峰团队的记为同学弘扬“砥砺自为”的校训精神,在周末自觉抵制网络游戏,发挥QQ群的正能量作用开展“共探共享”自主研究性学习活动,这是他们以人教A版教学必修一﹣P82.8题中的函数:f(x)=lg
1
-
x
1
+
x
为基本素材,取得的部分研究结果:
①QQ好友”通过乡下富起来“发现:函数f(x)的定义域为(﹣1,1);
②QQ好友“南江红叶红起来”发现:对于任意a,b∈(﹣1,1),都有f(a)+f(b)=f(
a
+
b
1
+
a
b
)恒成立;
③QQ好友“巴中二环通起来”发现:函数f(x)是偶函数;
④QQ好友“平昌水乡美起来”发现:函数f(x)只有一个零点;
⑤QQ好友“恩阳机场飞起来”发现:对于函数f(x)定义域中任意不同实数x1,x2,总满足
f
x
1
-
f
x
2
x
1
-
x
2
>0.其中所有的正确研究成果的序号是____ 
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How to Age Well

    Getting older is inevitable, but you can slow the decline of aging with smart choices along the way. From the foods you eat and how you exercise to your friendships, it all has an effect on how fast or slow your body ages.____

Lose just a little bit of weight.

    Small changes in body weight can have a big impact on health risks.____While we'd love to lose our extra pounds, it's easier to start with a 5 percent weight loss goal and keep on.

Avoid processed meat.

    ____A number of studies have found associations between eating a lot of processed meats and poor health. Other research has implicated processed meats in a higher risk for cancer. But there was no increase in risk associated with eating unprocessed red meat.

____

    The best eating strategy for aging well is to skip processed foods and drinks. That will immediately reduce added sugars from your diet. Once you cut out packaged foods, you will start eating a lot more fruits and vegetables, lean meats and fish and whole grains.____

    Meanwhile, invest in a new pair of walking shoes, a gym membership or a delicious healthy meal with your family and oilier loved ones. All of those are likely to do much for your emotional and physical health.

A. Skip packaged foods.

B. Save the money you would spend on rich food.

C. And the good news is that it's never too late to get started.

D. This has been shown in numerous studies to be good for you.

E. There's some evidence that vitamin B12 is good for the aging brain.

F. Losing just 5 percent of your body weight has been shown to reduce your risk for diabetes and heart disease.

G. Processed meals like hot dogs and sausages have been salted, cured or smoked to improve preservation.