# Maths Integration Problem! HELP

1. Jun 19, 2007

### susperia_knvb

Maths Integration Problem! HELP!!

1. The problem statement, all variables and given/known data
ok maths problems is like this:
2.g. integrate (2x-1)/*square root x*

3. The attempt at a solution

ok. i split the equation up so that i am integrating 2x/*root x* - 1/*root x*

the 1/root x integrates to - 2x^(1/2) and the constant is present (+c)

but i cannot seem to integrate the (2x)/(x^(1/2))
the answer is (4/3)x^(3/2)... but i cant seem to get it... even working backwards.

2. Jun 19, 2007

### arunbg

Can you simplify $$\frac{x}{\sqrt{x}}$$ ?

3. Jun 19, 2007

### susperia_knvb

take the two out the front of the integral sign and then multiply?

4. Jun 19, 2007

### susperia_knvb

ok. i dont get where the x^(3/2) comes from.
$$\frac{x}{\sqrt{x}}$$
becomes x.x^(-1/2)... then we add the powers?
= x^(1/2)?

5. Jun 19, 2007

### arunbg

Yes, correct. Can you integrate now?

6. Jun 19, 2007

### arunbg

Yes, correct. Can you integrate now?

7. Jun 19, 2007

### susperia_knvb

x^(1/2) becomes (2/3)x^3/2) then multiplying in the two becomes....

(4/3)x^(3/2) which is correct yeh?

cool :D

ok another one. (1-4x)/(x*root*x)... i cant do the (4x)/(x^(3/2))

8. Jun 19, 2007

### Gib Z

$$4 \cdot \frac{x}{x^{1.5}}= 4 \cdot x^{-1/2}$$

9. Jun 19, 2007

### susperia_knvb

damn it. lol. how stupid of me. missed the cancelling there totally. ah! no wonder i could do the rest of the chapter *shakes head*

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