1. ## Questions in derivatives

2. Once you have the slope, identify a point on the graph and use this formula $\displaystyle y-y_1=m(x-x_1)$

3. Originally Posted by r-soy

You have miscalculated.

$\displaystyle \displaystyle\ x^{-\frac{1}{2}}=\frac{1}{1.5}\Rightarrow\frac{1}{x^{\ frac{1}{2}}}=\frac{1}{\sqrt{x}}=\frac{1}{1.5}$

$\displaystyle \displaystyle\sqrt{x}=1.5\Rightarrow\ x=1.5^2$

4. Now X = 2.25

when I try found (y) I don't get the answer I don't now why >>

y = (2.25) - 3 (2.25)^1/2
=-1.125 this answer not as on my book

Also what is the range of values of curve's slop ?
(-in,1] is this correct ?

plese help me

5. Originally Posted by r-soy

y = (2.25) - 3 (2.25)^1/2
=-1.125 this answer not as on my book
check again,

$\displaystyle y= 2.25-3\sqrt{2.25} = -2.25$

6. but when I do here different answer y = (2.25) - 3 (2.25)^1/2

7. $\displaystyle y= 2.25-3\sqrt{2.25}$

$\displaystyle y= 2.25-3\times 1.5$

$\displaystyle y= 2.25-4.5$

$\displaystyle y= -2.25$

8. I know my dear it will come in that equation but when I do here y = (2.25) - 3 (2.25)^1/2 I got diffrent answer .

9. What do you mean "when I do here"? Are you saying you get something other than 2.25 for y? If so you are doing the arithmetic wrong!