Question

Please help
The following graph describes function 1, and the equation below it describes function 2:

Function 1

graph of function f of x equals negative x squared plus 8 multiplied by x minus 15

Function 2

f(x) = −x2 + 2x − 15

Function ____ has the larger maximum.
(Put 1 or 2 in the blank space)

Answer 1

graph of function f of x equals negative x squared plus 8 multiplied by x minus 15

So is it -x^2+8*(x-15)

Answer 2

do you agree?

Answer 3

yes

Answer 4

\[Funtion 1: -x ^{2}+8x-120\]
\[Function 2: -x ^{2}+2x-15\]

Looking at maximum values ....we could differentiate it and equal it to zero? or we could factorise it. may i know thw topic please?

Answer 5

quadric models

Answer 6

quadratic sry

Answer 7

in that case we can factorise it and see which function has the larger maximum
(Or draw the functions)

Answer 8

ok

Answer 9

or look at y intercepts.. the first function crosses y axis at- 120 where as the second function crosses at y axis -15 .. so the first one is more 'below' than the second.

Answer 10

ok

Answer 11

I didnt really understand this topic XD im kinda stupid

Answer 12

@marigirl

Answer 13

from the question what i can sort of gather is that we are looking at the values right.. at which point is their maximum ?
if your allowed to use a graphics calculator you can see the following information:

Answer 14

so i guess we can look at the corresponding y-values and see that Function 2 has a higher y value ? I hope i am doing this correct.. is there any way to check it?

Answer 15

no but u were really helpful!!!!

Answer 16

and if we sketch both in same graph , function will sit above function 1, meaning function 2 has a larger maximum

Answer 17

alright thx for all the help!!!!!

Answer 18

cool