#Is this the correct way to do this?

39 messages · Page 1 of 1 (latest)

tired bluff
silk snowBOT
tired bluff
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i think my work is wrong but i still got the right answer anyway

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assuming m+1/(m-1) >0 is wrong i think but idk what would be the correct way to do this

broken barn
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you still haven't set the range

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they just want to know the range of m

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you have found one awnser

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m > 1

hot mantle
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Isn't that a suitable 'range' for m

digital solar
livid crag
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(1,inf)

livid crag
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i got (x-2m)^2+m+1/(m-1)>0

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just find minimum of that

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you get a quadratic in m

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graph thr numerator

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then solve the denominator part

digital solar
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Is x fixed or variable?

tired bluff
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@livid crag the minimum of (x-2m)^2 is 0 so would you just get 0+m+1/(m-1)>0 and do what i did there?

fleet cypress
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which means the quadratic is bounded to above or below x-axis

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for which you'll get m + 1/m-1 > 0

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you can easily get the range of m then

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it just needs to avoid [1,-1]

tired bluff
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is this right?

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i used a discriminant trick to find range of -m - 1/(m-1)

fleet cypress
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or negative

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since if you put m < -1, you'll only get positive values for the f(x) for any x

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m > 1

tired bluff
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the answer key says m>1 is correct but in the my first attempt my work is wrong but somehow still got the right answer

fleet cypress
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you just to find the values of m where f(x) has no real zeros

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one case for the upper quadrants and one case for the lower quadrants

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since log_3 isn't defined for negative numbers yeet the range that gives the lower quadrant range

tired bluff
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.close thx guys