Question

ex 2 și 4 punctul b

Answer 1

2)
x+1/x=3 
Ridicam la patrat si avem:
x^2+1/x^2+2*x*1/x=9
x^2+1/x^2+2=9
x^2+1/x^2=7
4) b)
Conform punctului a) avem:
E(x)=(2x-1)^2
E(√2)=(2√2-1)^2=8-4√2+1=9-4√2
E(-√2)=(-2√2-1)^2=8+2*(-2√2)*(-1)+1=9+4√2
1/E(√2)=1/9-4√2=9+4√2/(9-4√2)(9+4√2)=9+4√2/49
1/E(-√2)=1/9+4√2=9-4√2/(9-4√2)(9+4√2)=9-4√2/49
1/E(√2)+1/E(-√2)=9+4√2+9-4√2/49=18/49

Answer 2

Rezolvarea in atașamente. Bonus 3.ul.:)