x+1/x=1 , then find the value of x^3 + 1
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Step-by-step explanation:
1
If x+1/x=3,then what will be the value of x?
Case 1:
x+1x=3
x+1=3x
2x=1
x=12
Case 2:
x+1x=3
x2+1x=3
x2−3x+1=0
x=−(−3)±(−3)2−4(1)(1)√2⋅1
x=3±5√2
If you take it as (x+1)/x = 3, then
x+1 = 3x, or
2x = 1, or
x = 0.5
Check: (0.5+1)/0.5 = 3. Correct
If you take it as x + (1/x) = 3, then
x^2–3x+1 = 0
x1 = [3+(9-4)^0.5]/2 = [3+5^0.5]/2 = 2.618033989.
x2 = [3-(9-4)^0.5]/2 = [3–5^0.5]/2 = 0.381966011.
Check: x1+(1/x1) = 2.618033989+(1/2.618033989) = 3. Correct.
x2+(1/x2) = 0.381966011+(1/0.381966011) = 3. Correct.
x1 = 2.618033989.
x2 = 0.381966011.
Answered by
0
Answer:
x+1/x=1
(x+1/x)³=x³+1/x³+3x. 1/x(x+1/x)
1³=x³+1/x³+3(1)
1-3=x³+1/x³
x³+1/x³=-2
HOPE THIS HELPS
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