### All Discussions (31)

### The body is the hero

Hello guys,

I was chatting earlier today and someone told me that science must be considered the hero of our time mainly when it comes to our immune system. Thenceforth, I decided to post exactly what I have learned from the past few days and I hop

Read more…### Geometry (I)

Imagine that we have 2 parallel lines and there are 5 points on each line.

How many triangles can we make by them?

1- 100

2- 200

3- 150

4- 300

Read more…### Let's study "Mathematics" with each other! (8)

**Lim ([x]+[x^2]+…+[x^100])=?** (Where **x****→ō** )

**-50****0****50****100**

### Let's study "Mathematics" with each other! (6)

1.

If:

**f(x)=** ** x , for x≤1 **& ** x^2 ,for x>1**

** **

Then,

What is the **inverse** of **f(x)**?

** **

1- **x , for x≤1 & √x ,for x>1**

2- **-x , for x≤1 & -√x ,for x>1**

3- **1/x , for x≤1 & 1/x^2 ,for x>1**

4- **-1/x , for x≤**

### Let's study "Mathematics" with each other! (5)

If we have:

**f(x)=****√{1-√(x-1)}**

Then,

Which one is the **range** of **f(x)**?

1- **[0,1]**

2- **[0,3/2)**

3- **[1/2,1[**

4- **[1/2,3/2)**

### Let's study "Mathematics" with each other! (7)

1.

**sin-1 x + cos-1 x=?**

** **

1- **π/4**

2- **π**

3- **π/2**

4- **2π**

******* ******* ******* ******* *******

2.

If,

**-π/2 < Ө < π/2**

**Sinhx= tgӨ**

Then,

**Coshx=?**

1- **cos Ө**

2- **csc Ө**

3- **sec Ө**

4- **sin Ө**

** **

******* ******* ***

Read more…### Let's study "Mathematics" with each other! (2)

1-If we have:

**[x]** **≤ (x/2)**

** **

Then which one is right?

1- **{x: x>1}**

2- **{x: x<1}**

3- **{x: -1<x<1}**

4- **{x: -2<x<0}**

******* ******* ******* ******* *******

2-Which one is **odd**?

1- **Ln {x+**√**(1+x ^{2})}**

2- **e^sinx**

3

Read more…### Let's study "Mathematics" with each other!

Hi dear friends!

How are you?

Are you interested in "Math"?!

So…

Let's study it together!

Please answer these questions:

1- If we have:

**1< (2|x|-1)/|x|+1 < 2**

Then;

Which one is right?

1) ** x > 1/2**

2)** -2 < x < 2**

3) ** x < -(1/3) or x > (1/3)**

4

Read more…### Let's study "Mathematics" with each other! (4)

1- If we have:

**f(x)= x ^{^2}+2x**

**g(x)=x ^{^3}**

^{ }

Then, how many answers can **(gof)(x)=(fog)(x)** have?

1- **1**

2- **2**

3- **3**

4- **6**

******* ******* ******* ******* *******

2- If we have:

**f(x)=2[x]+2[-x]**

** **

Then, what is

Read more…### Let's study "Mathematics" with each other! (3)

If we have:

**f(x)= Ln(x^ ^{9)}**

**g(x)=** **x^( ^{2/3)}**

**h(x)= e^( ^{x)}**

Then, what is **f(g(h(x)))**?

1- **6x**

2- **9x**

3- **10x**

4- **e^( ^{9x)}**

### Asteroid Towards Earth

Any idea or information about asteriods chances of hitting earth within a next decade.Sources : NASA Website

Read more…