Question

a) Aflati x daca (x√3 + 1)² - 3 (x - 2) (x + 2) = (2√3 + 5)²
b) Daca x = solutia ecuatiei de la punctul a aflati 2x⁻¹ - 1 = .........

Answer 1

3x²+1+2√3x-3x²+12=12+25+20√3
1+2√3x=25+20√3
2√3 x=24+20√3|:2
√3 x=12+10√3 |:√3
x=12:√3+10
x=4√3 +10

x^(-1) =1/(4√3+10)=1/(10+4√3)=(10-4√3)/(100-48)=(10-4√3)/52=
            = (5-2√3)/26
2x^(-1)=(5-2√3)/13

2x^(-1) -1= (5-2√3-13)/13=- (8+2√3)/13