14. i) If x +1/x = 4,find x2+ 1/x2 ​

Question

14. i) If x +1/x = 4,find x2+ 1/x2

in progress 0
Gianna 2 weeks 2021-09-10T13:49:16+00:00 1 Answer 0 views 0

Answers ( )

    0
    2021-09-10T13:50:54+00:00

    x +  \frac{1}{x}  = 4 \\ s.o.b.s \\ squaring \: on \: both \: sides \\  {(x +  \frac{1}{x}) }^{2}  =  {(4)}^{2}  \\ we \: know \: that \:  {(a + b)}^{2}  =  {a}^{2}  +  {b}^{2}  + 2ab \\  {x}^{2}  +   \frac{1}{ {x}^{2} }  + 2(x)( \frac{1}{x} ) = 16 \\  {x}^{2}  +  \frac{1}{ {x}^{2} }  + 2 = 16 \\  {x}^{2}  +  \frac{1}{ {x}^{2} }  = 14

Leave an answer

Browse
Browse

18:9+8+9*3-7:3-1*13 = ? ( )