SOLUTION: If x=3-4√2,then the value of x+1/x Will be A) 3+√2 B) -4√2 C) 6 D) None

Algebra ->  Numeric Fractions Calculators, Lesson and Practice -> SOLUTION: If x=3-4√2,then the value of x+1/x Will be A) 3+√2 B) -4√2 C) 6 D) None      Log On


   

Question 1133981: If x=3-4√2,then the value of x+1/x Will be
A) 3+√2
B) -4√2
C) 6
D) None
Found 2 solutions by Alan3354, MathLover1:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
If x=3-4√2,then the value of x+1/x Will be
------
Is it (x+1)/x ?
or x + (1/x) ?

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
If x=3-4sqrt%282%29,then the value of %28x%2B1%29%2Fx will be
%283-4sqrt%282%29%2B1%29%2F%283-4sqrt%282%29%29
%284+-+4+sqrt%282%29%29%2F%283+-+4sqrt%282%29%29.......multiply by the conjugate %283%2B4+sqrt%282%29%29 and apply minus-plus rules

%284+%28sqrt%282%29+-+5%29%29%2F%283%5E2+-+%284sqrt%282%29%29%5E2%29.... apply minus-plus rules
%28-4%285-%28sqrt%282%29%29%29%29%2F%28-%284sqrt%282%29%29%5E2-3%5E2%29....simplify:%284sqrt%282%29%29%5E2-3%5E2=23
4%285-sqrt%282%29%29%2F23
%284%2F23%29+%285+-+sqrt%282%29%29

in case you have x%2B1%2Fx=3-4sqrt%282%29%2B1%2F%283-4sqrt%282%29%29 you will get
%286%2F23%29%2811+-+16sqrt%282%29%29

so, in both cases answer is : D) none