#a-level functions question

61 messages · Page 1 of 1 (latest)

quiet moonBOT
final cradle
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they are not saying that?

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they are saying its -1/2x + 12 for that domain

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since those are the points given to u

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yeah

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cuz u only need to find g(g(0))

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u can make a piecwise function for the whole thing, but its not needed really

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we are not saying its greater than or equal to 0

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tho we can also deduce that

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its saying that the function g(x) that they have come up with, is defined over 0 to 14

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maybe u r confusing x and y?

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ik

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yeah, cuz they dont care about the left side

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left one does

clever owl
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but they used the right side

final cradle
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no, cuz u dont need it

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u are confusing x and y again

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u have to compute gg(0)

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gg

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so u dont care if its positive or whatever

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whats g(0)?

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and whats g(12)

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?

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u can legit forget about the left side of the graph

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then its just a linear function

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u can get the slope using the formula

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and ur intercept is already there

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yeah

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and u dont really need or care about the left side

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sure

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left side includes 0

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its just when u write a piecewise function, the decision is arbitrary

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then u did something wrong

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ur left side would be y = mx + 12

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u substitue 0 as x

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and u would get y = 0 + 12

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=12

clever owl
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so its y = -20x + 12

final cradle
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or vice versa

final cradle
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u subs 0 for x

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yep

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why do u want 6?

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forget about gg(0)

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u cant get gg(0) from the left part

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u can get g(0)

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but not gg(0)

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cuz g(0) = 12

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and the left part is only defined for values of x up to 0

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so the left part is undefined at g(12)

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it can

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if u want it

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which one?

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right one is defined for values of x greater than or equal to 0

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left one is -5 <= x <= 0

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right one is 0 <= x <= 14

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cuz g(12) cant be gotten from the left side

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u would have undefined

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yeah

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u r welcome