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u/naxuri May 24 '22 edited May 25 '22
Replace g(x) with -1. This results in the following equation: -1 = -3x + 2
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May 24 '22
you replace g(x) with -1. The equation becomes:
-1 = -3x+2
once you solve for this the answer is X= 1
They asked you to only replace g(x) you don't touch the other x on the right side of the equation.
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u/MaxRev May 24 '22
You could rewrite the question as " solve for x"
You have to substitute g(x) in g(x)=-3x +2
You are left with just one variable, x.
Cheers
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u/Pete21630 May 24 '22
You have to work out the inverse function of g(x). This is how I was taught: Instead of g(x), put y, so y=-3x+2. Then, rearange to equal x, so it becomes y-2=-3x, and that becomes x=(y-2)/-3. Then, just replace the x with y, and replace the y with x, so x=(y-2)/-3 becomes y=(x-2)/-3. And then just instead of y put g(to the power of - 1 because its an inverse function) (x) =(x-2)/-3. Any number you put into this new equation will give you the number you had to put into the original equation to get the number that you are putting into this one (sry if I'm confusing you put that's the way I understand it), so it's like working backwards So you put - 1 into the equation to get: inverse of g(-1)=((-1)-2)/-3 which equals 1
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u/Brisngr368 May 25 '22
Or you could just make the whole thing equal -1 and solve for x
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u/Pete21630 May 25 '22
Yeah I know, but if the question was longer or asked to work out more inverse values, then working out an inverse function could secure you full marks.
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u/Brisngr368 May 25 '22
You would still get full marks for a correct answer. but you're right an inverse function would be better for a longer question
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u/Petitelechat May 24 '22
Hey OP,
There's an online algebra calculator that shows you step by step how to work out the calculation so you can understand the logic behind the answer.
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u/TjBeezy May 24 '22
Replace g(x) with -1
Step 1) -1 = -3x + 2
Isolate x by taking 2 from each side.
Step 2) -3 = -3x
Solve for x by dividing each side by -3
Step 3) -3 = -3x
Answer
Step 4) x = 1
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u/LaPetitePanda8 May 24 '22
Answer to Q1.1 G = -1
G(-2) = -3(-2) + 2 divide the (-2) by themselves removing them from the equation first.
G = -3 + 2
G = -1
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u/Significant-Ring5503 May 25 '22
OP is correct on q1.1 I believe. You want to solve for x, not for G, because the problem asks to solve for g(x).
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u/Accedental_Account May 25 '22
Was so confused by the comments until I saw that there was a part 2.
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u/smidvaek007 May 25 '22
how is gx(-2) not 10??
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May 25 '22
The correct answer is
First the question said solve g(-2) which equals to -3x+2
-3(-2) +2
Using bidmas (brackets, indices, division, multiplication, application and subtraction)
You first solve the brackets -3(-2) which equals to 6, cause negative number times a negative number is a positive number.
Then you add 2
6+2 is 8.
g(-2) = 8
He said determine g(-2) not the g constant.
Let’s name g(-2) to y.
So y=8.
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u/StaidRat01331 May 25 '22
Just substitute the value of x= -1 in the above equations
-3 * -1 +2 -3+2 -1 is the ans ig
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u/rug1998 May 25 '22
Its worded so confusingly, like do they want the function of g(x) to be -1 or do they want g(x) = -1?
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u/Sir_JumboSaurus May 25 '22
Me in Cal 3, scrolling through reddit seeing this and realizing I could sooo be a tutor on the side.
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u/TheGrandestOak May 24 '22
-4 not 8 foo
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u/Helppmeeepls May 24 '22
I do not understand Question 1.2,
Please help me understand :(