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-Find all values of k for which the equation 3x^2−4x+k=0 has no solutions.

 

 

-What is the value of m, if the equation my^2+2y−4=0 has exactly one root?

 

i don't get it I don't get it somebody help ahhhhh i can't take it anymore

 Apr 13, 2016
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3x^2 - 4x + k  =  0      will always have solutions.....but....if you mean real solutions, we can use the discriminant  to find the values of k that produce these

 

(-4)^2 - 4(3)k  ≥  0

 

16 - 12k ≥  0     divide through by 4

 

4 - 3k ≥  0      add 3k to both sides

 

4 ≥ 3k       divide both sides by 3

 

4/3 ≥ k    .......this means that k must be ≤ 4/3 for the function to have real solutions

 

 

 

my^2 + 2y - 4 = 0  ....we need to find the value of m that makes the discriminant = 0

 

(2)^2 - 4(m)(-4) =  0

 

4 + 16m =  0      divide through by 4

 

1  + 4m = 0      subtract 4m from both sides

 

1  = -4m      divide both sides by -4

 

-1 / 4 =    m     

 

Thus.....the given function will have exactly one root  [ of a multiplicity of 2]  when m = -1/4

 

 

 

cool cool cool

 Apr 13, 2016

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