Question

Determinati solutiile reale ale ecuatiei: 2x^2-7x+5=0

Answer 1

2x^2-7x+5=0

d-delta 

d=-(-7)-4*5*2=49-40=9
x1=(7+3)/2a=10/2*2=10/4=5/2
x2=(7-3)/2a=4/4=1

Answer 2

 2x² - 7x + 5 = 0     → ec. de gr. II.

Folosim formulele: [tex]delta=b^2-4ac\\ x_1,x_2= \frac{-b(+~sau~-) \sqrt{delta} }{2a} \\ unde~a=2,b=-7,c=5[/tex]

Rezolvare: [tex]delta=(-7)^2-4*2*5\\ delta=49-40\\ delta=9\\\\ x_1= \frac{-(-7)+ \sqrt{9} }{2*2} =\ \textgreater \ x_1= \frac{7+3}{4} =\ \textgreater \ x_1= \frac{10}{4} (simplificam)=\ \textgreater \ x_1= \frac{5}{2} \\\\ x_2= \frac{-(-7)- \sqrt{9} }{2*2} =\ \textgreater \ x_2= \frac{7-3}{4} =\ \textgreater \ x_2= \frac{4}{4} =\ \textgreater \ x_2=1[/tex]

Scriem solutiile: {1 ; 5/2}