Ask your own question, for FREE!
Mathematics 10 Online
OpenStudy (liv1234):

Can someone please help me with a question?

OpenStudy (liv1234):

OpenStudy (michele_laino):

the new function g(x) has to be equal to the old function f at point x+1

OpenStudy (liv1234):

What does that mean?

OpenStudy (michele_laino):

in formula, my statements means: g(x)=f(x+1)

OpenStudy (liv1234):

So kind of like for example y= mx+b?

OpenStudy (michele_laino):

in that case, we can write this: g(x9=m(x+1)+b

OpenStudy (michele_laino):

oops.. g(x)=m(x+1)+b

OpenStudy (liv1234):

By the way, sorry if I seem slow with this, I'm just really bad with math.

OpenStudy (michele_laino):

no worries! :)

OpenStudy (liv1234):

So, g(x)=m(x+1)+b

OpenStudy (michele_laino):

yes!

OpenStudy (liv1234):

How would I solve the answer with that?

OpenStudy (michele_laino):

I think you have to do the multiplication, like below: g(x)=mx+m+b

OpenStudy (liv1234):

How do I do the multiplication with this equation?

OpenStudy (michele_laino):

we can do the multiplication above using the distributive property of multiplication over addition

OpenStudy (liv1234):

I think I remember how to do that, is there a formula?

OpenStudy (liv1234):

So, (sorry to ask again) what numbers would be put in?

OpenStudy (michele_laino):

the general formula, is: \[\left( {a + b} \right)c = ac + bc,\quad \forall a,b,c \in \mathbb{R}\]

OpenStudy (michele_laino):

you have to know the values of the coefficients m and b

OpenStudy (liv1234):

I feel really stupid to keep asking for help, but how would I find the coefficients?

OpenStudy (michele_laino):

you can retrieve the value of those coefficients, from the text of your exercise

OpenStudy (liv1234):

The only number I had from the exercise is "1"

OpenStudy (michele_laino):

in that case your exercise is not a numeric exercise

OpenStudy (liv1234):

Hang on, let me repost the question

OpenStudy (michele_laino):

ok!

OpenStudy (liv1234):

OpenStudy (liv1234):

Okay, that's the question

OpenStudy (michele_laino):

your answer, is: \[g\left( x \right) = m\left( {x + 1} \right) + b = mx + m + b\] and we have completed your exercise

OpenStudy (liv1234):

Wait, so what option would I choose? I'm confused.

OpenStudy (michele_laino):

the first option

OpenStudy (liv1234):

Can you help me with another question?

OpenStudy (michele_laino):

ok!

OpenStudy (liv1234):

OpenStudy (michele_laino):

when we make a reflection with respect to the x-axis, then we can write the new function g(x) as below: \[g\left( x \right) = - f\left( x \right)\]

OpenStudy (liv1234):

So, how would I solve?

OpenStudy (michele_laino):

it is simple, you have to replace f(x) with its formula: \[g\left( x \right) = - f\left( x \right) = - \left( {{x^2} + 5} \right) = ...?\]

OpenStudy (liv1234):

Would the answer be g(x)= -x^2+5?

OpenStudy (michele_laino):

not exactly, since when you cancel the parentheses, you get this: \[g\left( x \right) = - f\left( x \right) = - \left( {{x^2} + 5} \right) = - {x^2} - 5\]

OpenStudy (liv1234):

I'm confused D:

OpenStudy (michele_laino):

every term inside the parentheses change its sign

OpenStudy (michele_laino):

so we can write this: \[ - \left( {{x^2} + 5} \right) = - {x^2} - 5\]

OpenStudy (liv1234):

So, the first option?

OpenStudy (michele_laino):

yes!

OpenStudy (liv1234):

Can you help me with another one?

OpenStudy (michele_laino):

ok!

OpenStudy (liv1234):

OpenStudy (michele_laino):

here we have to consider all points whose y-coordinate is less the y coordinate of the points which belong to the straight line

OpenStudy (liv1234):

Let me guess, it's the first option right?

OpenStudy (liv1234):

Or is it another one?

OpenStudy (michele_laino):

please wait, first we have to write the equation of the straight line

OpenStudy (liv1234):

Okay, so how would we do that?

OpenStudy (liv1234):

I know that the line is at -6 and 5

OpenStudy (michele_laino):

your line passes at points (-5,0) and (0,6), so its equation is: \[\frac{{y - 0}}{{6 - 0}} = \frac{{x + 5}}{{0 + 5}}\]

OpenStudy (liv1234):

It actually passes at -6 and 5 though.

OpenStudy (michele_laino):

which can be simplified to this form: \[6x - 5y = - 30\]

OpenStudy (liv1234):

So, what option would I choose?

OpenStudy (michele_laino):

please wait, I think that your line passes at points (-6,0) and (0,5), so its equation is: \[5x - 6y = - 30\]

OpenStudy (liv1234):

So, would it be C or D?

OpenStudy (michele_laino):

so the shaded part of cartesian plane is represented by this inequality: \[5x - 6y \geqslant - 30\]

OpenStudy (liv1234):

So, D?

OpenStudy (liv1234):

Can you help me with another one please?

OpenStudy (michele_laino):

more explanation: the y-coordinate of the points of the shaded region has to be less than the y-coordinate of the point of the straight line, so we can write this: \[y \leqslant \frac{{5x - 30}}{6}\]

OpenStudy (liv1234):

Can you help me with this question?

OpenStudy (liv1234):

Please?

OpenStudy (michele_laino):

we can write this: \[g\left( x \right) = 5\left( { - 7{x^2}} \right) + 5 = 5f\left( x \right) + 5\]

OpenStudy (liv1234):

I think the answer is D

OpenStudy (michele_laino):

yes! correct!

OpenStudy (liv1234):

Yay! Can you help me with another one please?

OpenStudy (michele_laino):

ok!

OpenStudy (liv1234):

OpenStudy (liv1234):

Okay, that's the question.

OpenStudy (michele_laino):

the y-coordinates of the new function g(x) have to be six time greater than the respectively y-coordinate of the old function f(x)

OpenStudy (liv1234):

So, would the answer be C?

OpenStudy (michele_laino):

no, I meant six as a factor

OpenStudy (liv1234):

Oh, so would it be A? Because it has multiplication?

OpenStudy (michele_laino):

correct!

OpenStudy (liv1234):

Can you help me with another one?

OpenStudy (michele_laino):

please wait, since another student has requested my help

OpenStudy (liv1234):

It's a quick question though

OpenStudy (michele_laino):

ok!

OpenStudy (liv1234):

OpenStudy (michele_laino):

-7 means shifting down by 7 units furthermore, as we can see in your first exercise, x+3 means shifting to left

OpenStudy (liv1234):

So, would it be C?

OpenStudy (liv1234):

Oh, wait, B?

OpenStudy (michele_laino):

no, since the vertical shift is by 7 units down and the horizontal shift is by 3 units left

OpenStudy (liv1234):

So, B?

OpenStudy (michele_laino):

correct! it is option B

OpenStudy (liv1234):

Do you think you could help me with another?

OpenStudy (michele_laino):

yes! please wait

Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!
Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!