All Answers 355923 Answers

What is x-5/x+7 - 3x2 when x=-2?

\(x=-2\)

\(x-\frac{5}{x}+7-3x^2\) = \(\frac {4-5-14+24}{-2}\) =  \({\color{blue}- 4\frac {1}{2}}\)

\(\color{blue}= \frac{\left(x-1\right) ^{2}\times \left(x+\frac{5}{3} \right) }{x} \)

asinus :- )   !

Learn how to use brackets, so that there is no ambiguity as to you want.

This could mean:(3a^2bc)/(2b) -3c - bc/a, or could mean:(3a^2bc)/(2b-3c) - bc/a, or could mean:

(3a^2bc) / [(2b-3c) - (bc/a)]. All these might or will give you different answers. So, don't be surprised if you get a different answer from what you expect, or is in your book.

Txs whoever u r

4/3 or 1 1/3

Evaluate (3 a^2 (b c))/(2 b)-3 c-(b c)/a where a = -2, b = 3 and c = -5:
3 a^2 (b c)/(2 b)-3 c-(b c)/a = 3×(-2)^2×(-5×3)/(2×3)--5×3-(-5×3)/(-2)

3×(-2)^2×(3 (-5))/(2×3) = (3 (-5) 3×(-2)^2)/(2×3):
(-5×3×3×(-2)^2)/(2×3)--5×3-(-5×3)/(-2)

(3 (-5) 3×(-2)^2)/(2×3) = 3/3×(-5×3×(-2)^2)/2 = (-5×3×(-2)^2)/2:
(-5×3×(-2)^2)/2--5×3-(-5×3)/(-2)

(-2)^2 = 4:
(-5×3×4)/2--5×3-(-5×3)/(-2)

4/2 = (2×2)/2 = 2:
-5×3×2--5×3-(-5×3)/(-2)

3 (-5) = -15:
-5×3×2--5×3--15/(-2)

The sign of (-15)/(-2) is positive, so (-15)/(-2) = 1×15/2:
-5×3×2--5×3-15/2

-5×3 = -15:
-15×2--5×3-15/2

-15×2 = -30:
-30--5×3-15/2

-3 (-5) = 15:
-30+15-15/2

Put -30+15-15/2 over the common denominator 2. -30+15-15/2 = (2 (-30))/2+(2×15)/2-(15)/2:
(-30×2)/2+(2×15)/2-(15)/2

2 (-30) = -60:
-60/2+(2×15)/2-(15)/2

2×15 = 30:
(-60)/2+30/2-(15)/2

-60/2+30/2-15/2 = (-60+30-15)/2:
(-60+30-15)/2

-60+30-15 = 30-(60+15):
30-(60+15)/2
(30-75)/2

30-75 = -(75-30):
-(75-30)/2
Answer: |(-45)/2

Um, Chicken first? Probably yeah chicken first 'cause you said that before the egg. :)

Uh 400!? 😎 :)

Thanks - I use Google Chrome too so I guess it is not the browser that makes the difference ://

You are very welcome. :)   Welcome to the web2.0calc forum too Griel021    

Just check that that the question I answered is the one you really intended to ask.  :)

Or perhaps this was meant to be \(\frac{x+1}{x-1}+\frac{2x-1}{2x+1}\)

in which case we have \(\frac{-1}{-3}+\frac{-5}{-3}\rightarrow \frac{1}{3}+\frac{5}{3}\rightarrow \frac{6}{3}\rightarrow 2\)

If so, note that it's important to use brackets to remove possible ambiguity!

.

.

Thank you melody 😄😎

r^-3s^2t)^4

\((r^{-3}s^2t)^4\\ =r^{-3*4}s^{2*4}t^4\\ =r^{-12}s^{8}t^4\\ =\frac{s^{8}t^4}{ r^{+12} }\\ =\frac{s^{8}t^4}{ r^{12} }\\\)

What is x+1/x-1 + 2x-1/2x+1 when x= -2?

\(x+\frac{1}{x}-1 + 2x-\frac{1}{2}x+1\qquad \qquad when\quad x= -2?\\ =-2+\frac{1}{-2}-1 + 2*-2-\frac{1}{2}*-2+1\\ =-2-\frac{1}{2}-1 -4+1+1\\ =-2-1 -4+1+1-\frac{1}{2}\\ =-2 -4+1-\frac{1}{2}\\ =-5-\frac{1}{2}\\ =-5\frac{1}{2}\\ \)

Pls tell me what is the answer!

No, it's not zero!  As Melody wrote, 0/0 is undefined in mathematics (though there might be some computer languages that treat it as zero).

.

It depends like when the the problem is like this -(-number)= + positive

- -number= negative number 😂😄

Uh Duh it's 1,5, and 25

If the interest rate is 0% then the initial amount could be $15000 give or take $100 

That is one answer  :)

Uh duh 0 

It is undefined :)

The sum of squares from 1 to n is given by n(n+1)(2n+1)/6, so use this with n = 2011

.

Hmm! Possibly a typo:

Alan, I expected a precaution both possibilities.
Thanks for your comment!

asinus :- ) !

In the equation, tan θ = 3.2/7.5,      θ = ?

\(tan \theta =\frac{3.2}{7.5 }\)

\(\theta = arctan\ \frac{3.2}{7.5}\)

\({\color{blue}\theta = 23° 6' 23''}\)

asinus :- )   !

Oh, ok asinus, I see you have assumed the original might have been such that the 3 is not part of the exponent, which is strictly correct according to the normal hierarchy rules.  However, it's extremely unlikely that that is what is meant in this sort of question I could be wrong of course!).