×

# Hard Math!!

1.)If x^3-xyz=2 y^3-xyz=6 z^3-xyz=20 Find the maximun of x^3+y^3+z^3

2.)If x^2+y=12=y^2+x Find x^2+y^2

*3.) x=(1/sqrt2)+(1/sqrt3)+(1/sqrt4)+...+(1/sqrt1000) find the most Integer that small than or equal x.

Note by Areefil Raksanit
4 years, 2 months ago

MarkdownAppears as
*italics* or _italics_ italics
**bold** or __bold__ bold
- bulleted- list
• bulleted
• list
1. numbered2. list
1. numbered
2. list
Note: you must add a full line of space before and after lists for them to show up correctly
paragraph 1paragraph 2

paragraph 1

paragraph 2

[example link](https://brilliant.org)example link
> This is a quote
This is a quote
    # I indented these lines
# 4 spaces, and now they show
# up as a code block.

print "hello world"
# I indented these lines
# 4 spaces, and now they show
# up as a code block.

print "hello world"
MathAppears as
Remember to wrap math in $$...$$ or $...$ to ensure proper formatting.
2 \times 3 $$2 \times 3$$
2^{34} $$2^{34}$$
a_{i-1} $$a_{i-1}$$
\frac{2}{3} $$\frac{2}{3}$$
\sqrt{2} $$\sqrt{2}$$
\sum_{i=1}^3 $$\sum_{i=1}^3$$
\sin \theta $$\sin \theta$$
\boxed{123} $$\boxed{123}$$

Sort by:

areefil baeng

- 3 years, 6 months ago

The second math...is it have a condition for x and y? If they are both interger, you can just put the table and take your answer there!

- 4 years, 2 months ago

Sr, This is how I solve the second problem.

You have : x^2 +y = 12 x+y^2 = 12

Minus those 2, you will have : (x-y)(x+y-1) = 0 x=y=3 will be the answer so I won't do anything with it here.

So x+y = 1. Add those 2 equation up there, you will have : (x+y)^2 -2xy + x + y = 24

Replace x+y. Find xy. Use xy and x+y to know x and y. I think you won't find it...I don't really know!

- 4 years, 2 months ago

how do you know that its are =3?

- 4 years, 2 months ago

Do some math. Try to replace and find out. This works everytime if the number you are finding is not big (like from 1->10). When you have the answer, it is easier for you to figure how to do the math :)

- 4 years, 2 months ago