help

[serene palm]

#1224079587798028410 message

[near barn]

mhm

[near barn]

.

[serene palm]

Can we assume x ≥ 5?

Or I think we have to

[near barn]

answer should be (4;9), x∈N

[serene palm]

You can start with dividing by x! on both sides

[near barn]

whats next?

[little anchor]

adonhs

[serene palm]

What do you think is next?

[near barn]

move and try to co-name

[near barn]

.

[fresh kayak]

Co-name ?

[serene palm]

i dont understand your sentence

[near barn]

sorry, translator mistake

to make the denominators the same

[near barn]

.

[fresh kayak]

Do it then

Also, you could notice that these are two binomial coefficients

[serene palm]

I would multiply both sides by 5!(x-5)!

Notice this hint: ||(x-4)! = (x-4)(x-5)!||

[near barn]

so i got 1<5/(x-4)

[serene palm]

yes

Now since x > 4 what can you do next?

[near barn]

how?

[serene palm]

Because (x-5)! is defined x ≥ 5 or x > 4 if x is a natural number

factorial x! is defined for x ≥ 0

so (x-5)! is defined for x - 5 ≥ 0

which is x ≥ 5

[near barn]

but answer is (4;9), x∈N

[near barn]

.

[serene palm]

You are confusing the domain with the solutions of 1<5/(x-4)

Before you start solving an inequality or even equation you define which x are allowed

If you can't follow, then still solve the inequality and you will see

[near barn]

ok

[near barn]

.

[near barn]

and now i can multiply by x-4

[serene palm]

yes after decades

[near barn]

xxd

x<

X<9

[serene palm]

yea

so x < 9

but we also restricted x to be x ≥ 5

so the solution would be [5,9) or like yours (4,9)

since x is natural

[near barn]

.solved