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anonymous
 5 years ago
can someone help me!!??? please i would really appreciate it. question: If y=4x²+kx1determine the value(s) of k for which the maximum value of the function is an integer. Explain your reasoning using pictures, numbers, and words.
anonymous
 5 years ago
can someone help me!!??? please i would really appreciate it. question: If y=4x²+kx1determine the value(s) of k for which the maximum value of the function is an integer. Explain your reasoning using pictures, numbers, and words.

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amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0lets try this from the quad formula perspective... sqrt(k^2 4(1)(4)) would have to be equal to or greater than 0

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0k^2 16 >= 0 k^2 >= 16 k >= +sqrt(16) k>= 4, or 4

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0or rather k>= 4 ro 4...might be a better scenario :)

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0since 4x^2 gives us an upsode down "U" for a graph, we can determine the "largest value"... at the vertex: k/2(4)

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0k/8 = k/8 we have some value for "x" which is equal to k/8 can we use that in our equation?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0y=4(k/8)²+k(k/8)1 y = 4k^2/61 + k^2/8  1

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.061 = 64 in my world lol

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0y = 4k^2/64 + 8k^2/64 1 y = 4k^2/64  1 y = 4k^2/64  1 y = k^2/16  1 can we do anything with this "value"?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0or am I making this to hard on myself....

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.04x^2 +kx 1 = 0 factors to.. 4x^2 kx +1 = 0 1,4 = 4 2,2 = 4 (x 1)(4x 1) or (2x1) (2x1)

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0the values we get for the product of "ac" are: 4(1) = 4 1+4 = 5, k=5 in this instance 2+2 = 4, k=4 in this instance. but I might have a "sign" out of place so I would have to recheck it all :) but does that make sense?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0can we do this from the beginning again??

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0if y=4x^2 +k 1 dont we plug it into the discriminant?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0which beginning :) I was trying to determine a good manner in which to appraoch the problem...the discriminate there was not an "easy" way.... that I could see.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i mean from the beggining of the question...so far thats what i know

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0but the question states tht the value of the function is an integer so does tht mean that the value of k <0

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0its easier to approach from the "meaing" that is given to a,b, and c the "c" term is a product of 2 numbers; the "b" term is a sum of 2 numbers. for "b" to have the greatest value, the sum of the factors of "c" would have to combine to the biggest value right?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i have no idea what u just said?? lol

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0an integer is any number between infinity and +infinity... :)

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0the bigest integer value can p[ossibly be a negative value as long as it is the biggest integer we can get :)

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0but lets try this approach... first we factor out that 1 to make our lives easier: y = 1(4x^2 kx +1) we good here?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0we need to gather a "pool" of options for the middle term. that "pool" comes from the number we get when we multiply "a" and "c". 4 times 1 = 4. we good so far?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0wait when u r doing this r u plugging it into the discriminant??? or just doing it...?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0just doing it.... the discrimant is only valueable if you "know" what k is.... so lets continue on this path and see where it leads :)

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0we need two number: call them "m" and "n", that multiply together to get "4" and ADD together to get our value for "k". does that make sense?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0yes ur doing product n sum

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0correct: our options are: 4(1) = 4; 4+1 = 5 2(2) = 4; 2+2 = 4 which number is greater.... 4 or 5?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0the 2(2) seems reasonable..cuz u need greates common factor right??

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0we couldnt care less about "common" factors here :) what we care about is the greatest value that we can get for "k". the value for "k" is obtained by "adding together" the factors that make up "4". That is our only concern :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0so if we r looking for the greatest common value then we use the numbers 1 n 4...

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i mean the greatest value for k

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0thats right.... so lets see if 5 is a good answer by plugging it into our original formula and seeing what we get:) y = 4x^2 +(5)x  1 how would we TEST this situation?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0our "highest point" is at our vertex: b/2a 5/2(4) = 5/8 = 5/8 5/8...our "vertex is at 5/8. what is the value of y at x = 5/8?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0where did u get b/2a?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0that is from the quadratic formula as well.... do you know the quadratic formula?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i didnt tht it gives u the highest point at the vertex..

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0the quad formula says that the roots of a quadratic expression are equal distances from a certain value of x.... right? b sqrt(b^24ac)  + or   2a 2a right?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0so the cernter, or vertex, of our equation lies between these 2 points..... the x value of our "vertex" then must be b/2a.... am I right?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0if you move 5 feet to your left, or 5 feet to your right.... where is the middle of that?.... exactly where you were standing to begin with right?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0sqrt(b^24ac).......b.......+sqrt(b^24ac)    2a 2a 2a I hope this displays correctly lol

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0does that make sense?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i think i got it thanks i think i can handle it from here

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0ok :) but if this might clarify things a bit
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