Question

Determine as raizes da equação:
a) x² - 13x + 42 = 0
b)x² - 5x + 6 = 0
c)x² + 5x - 6 = 0
d)3x² - 2x - 1 = 0

Answer 1

Por bhaskara:
a) 13± √169-4*1*42 }÷2
13±1 ÷2
13+1= 14÷2 = 7
13-1= 12÷2 = 6
x'=7
x''=6

b) 5±√25-4*1*6 }÷2
5±1 ÷2
5+1= 6÷2 = 3
5-1= 4÷2 = 2
x'= 3
x''=2

c)-5±√25-4*1*(-6) }÷2
-5±√49 }÷2
-5±7 ÷2
-5+7= 2÷2= 1
-5-7= -12÷2 = -6
x'= 1
x''= -6

d)2±√4-4*3*(-1) }÷2
2±6 ÷2
2+6= 8÷2 = 4
2-6= 4÷2 = 2
x'=4
x"= 2