Melody

But why is  

  $$\\-1^2=-1 \;\;when\;\; -1*-1=+1\qquad $maybe you didn't know that?$$$

I have something for you to think about  MG

$$\\(-1)^2=1\\
$so would it be correct to say that$\\
\sqrt{1}=-1\;\;\;?\\
also\\
what \;is\;\; -1^2\;\;\;?$$

It is good to see you making good use of the web2 calc MG  :)

That was quite a feat Chris,  

I will do it using remainder theorem.

For what value of c will the polynomial P(x) = -2x^3 + cx^2 - 5x + 2 have the same remainder when it is divided by x - 2 and by x + 1?

When P(x) is divided by x-2 the remainder will be     p(2)=-2*8+c*4-10+2 = -16+4c-8 = 4c-24

When P(x) is divided by x+1 the remainder will be    p(-1)=-2*-1+c*1+5+2=2+c+7 = 9+c

If these are the same then 

4c-24=9+c

3c=33

c=11

1.000e+00? means  $${\mathtt{1}}{\mathtt{\,\times\,}}{{\mathtt{10}}}^{{\mathtt{0}}}$$  =   1*1 = 1

We agree, how unusual :)

Okay thanks Alan, I think I have digested that.  And I can see why Chris's answer makes sense.

BUT

I still would like to understand why my logic  is wrong :)

I have always thought with probability that it is often fairly easy to understand the correct answer but much harder to understand why an incorrect answer is wrong.

Still, with all the prob questions we have been getting I think my ability is improving :)

$$\\\frac{(4xy^{-3})^{4}}{(2x^{2}y^{-7})}\\\\
\frac{(4^4x^4y^{-3*4})}{(2x^{2}y^{-7})}\\\\
\frac{2*4^3x^4y^{+7}}{1x^{2}y^{+12}}\\\\
\frac{128x^{(4-2)}}{y^{(12-7)}}\\\\
\frac{128x^{2}}{y^{5}}\\\\$$

3.25-5 = -(5-3.25)=-(5-3-0.25)=-(2-0.25)=  -1.75