Find & simplify

[TSW]

I an algebra stupid..... I need specific / detailed steps of how to solve this problem:
Let g(x)=-x (squared) + 2x - 7 Find and simply g(1/2) ( one over two)

 

[Deleted member 4993]

I an algebra stupid..... I need specific / detailed steps of how to solve this problem:
Let g(x)=-x (squared) + 2x - 7 Find and simply g(1/2) ( one over two)

\(\displaystyle g(x) \ = \ x^2 + 2 * x -7 \)

replace 'x' by (1/2) and carry out the desired operations.

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[TSW]

Reply

Well regarding my original post -- if I had the slightest clue of how to start this problem or how to work it... I wouldn't be here. I know the answer is -25 over 4 - but don't have a clue how to get it

Originally Posted by TSW
I an algebra stupid..... I need specific / detailed steps of how to solve this problem:
Let g(x)=-x (squared) + 2x - 7 Find and simply g(1/2) ( one over two)



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replace 'x' by (1/2) and carry out the desired operations.

You need to read the rules of this forum. Please read the post titled "Read before Posting" at the following URL:

http://www.freemathhelp.com/forum/th...217#post322217

We can help - we only help after you have shown your work - or ask a specific question (not a statement like "Don't know any of these")

Please share your work with us indicating exactly where you are stuck - so that we may know where to begin to help you.

 

[HallsofIvy]

It sounds lie the difficulty in not algebra but arithmetic, then. You are given the function \(\displaystyle g(x)= -x^2+ 2x- 7\) and are asked to find g(1/2). The only algebra part is knowing what that means- and Subhotosh Khan told you that: "replace 'x' by (1/2) and carry out the desired operations."

Do you not know how to "replace 'x' by (1/2)? That is just \(\displaystyle g(1/2)= -(1/2)^2+ 2(1/2)- 7\). Literally, just write "1/2" in place of each "x".

Or do you not know how to do the arithmetic? \(\displaystyle -(1/2)^2= (-1)(1/2)(1/2)\). Can you do that multiplication?

2(1/2)= what?

Subtract 7 from that last number and add the first (both numbers added are negative so the result will be negative.)


And I recommend that you stop calling yourself "stupid". That tends to be a self- fulfilling prophesy.

 

[lookagain]

You are given the function \(\displaystyle g(x)= >> -x^3+ 2x- 7 < <\) and are asked to find g(1/2).

The only algebra part is knowing what that means- and Subhotosh Khan told you that: "replace 'x' by (1/2) and carry out the desired operations."

Do you not know how to "replace 'x' by (1/2)? That is just \(\displaystyle g(1/2)= -(1/2)^3+ 2(1/2)- 7\). Literally, just write "1/2" in place of each "x".

Or do you not know how to do the arithmetic? \(\displaystyle -(1/2)^3= (-1)(1/2)(1/2)(1/2)\). Can you do that multiplication?

The given function is \(\displaystyle g(x) = -x^2 + 2x - 7.\)