SOLUTION: (7)Question:
Solve: ^3 sqrt x^2-4x+2=^3 sqrt x+2
(a) 0,5
(b) 1/2, 5
(c) 0, 11/2
(d) 1/2, 11/2
Thanks for your help in advance!
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-> SOLUTION: (7)Question:
Solve: ^3 sqrt x^2-4x+2=^3 sqrt x+2
(a) 0,5
(b) 1/2, 5
(c) 0, 11/2
(d) 1/2, 11/2
Thanks for your help in advance!
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You can put this solution on YOUR website! ^3 sqrt x^2-4x+2=^3 sqrt x+2
Probably the question is
[sqrt (x^2-4x+2)]^3 = [sqrt (x+2)]^3 ----(1)
This implies
(x^2-4x+2) = (x+2)
[how? Please look at the model below]
x^2-4x-x+2-2 = 0 (grouping like terms)
x^2-5x = 0
x(x-5) = 0
x =0 or (x-5)=0 which gives x = 5
Answer: x = 0 or x = 5
Which is the choice (a) 0,5
Note: Let us evolve a model out of this
[sqrt(p)]^3 =[sqrt(q)]^3
[(p)^(1/2)]^3= [(q)^(1/2)]^3
[(p)^(3/2)]= [(q)^(3/2)] (using [(a)^m]^n =[(a)^(mn) ——(*)] )
Now raising both the sides to the power (2/3)
[(p)^(3/2)]^(2/3)= [(q)^(3/2)]^(2/3)
{(p)^[(3/2)X(3/2)]}= {(q)^[(3/2)X(3/2)]}
[(p)^1]= [(q)^1] ((using (*) )
That is p = q
Note: The above steps if we go through repeatedly then
we will be in a position to just observe and conclude
(