Resposta:
Explicação passo a passo:
a) x2+3x−54=0
(1)⋅x2+(3)⋅x+(−54)=0
x=−(3)±(3)2−4⋅(−54)−−−−−−−−−−−−−−√2
x=−3±9−(−216)−−−−−−−−−−√2
x=−3±225−−−√2
x=−3±(15)2
x1=122=(2)
⋅(6)(2)=6
x2=−182=(2)
⋅(−9)(2)=−9
b) x2−x+2=0
(1)⋅x2+(−1)⋅x+(2)=0
x=−(−1)±(−1)2−4⋅(2)−−−−−−−−−−−−−√2
x=1±1−(8)−−−−−−√2
x=1±−7−−−√2
c) −3x2−5x+1=0
(−3)⋅x2+(−5)⋅x+(1)=0
x=−(−5)±(−5)2−4⋅(−3)−−−−−−−−−−−−−−−√2⋅(−3)
x=5±25−(−12)−−−−−−−−−−√−6
x=−5±37−−√6
x1=−5+37−−√6
x2=−5−37−−√6
d) x2−5x+6=0
(1)⋅x2+(−5)⋅x+(6)=0
x=−(−5)±(−5)2−4⋅(6)−−−−−−−−−−−−−√2
x=5±25−(24)−−−−−−−−√2
x=5±1–√2
x=5±(1)2
x1=62=(2)
⋅(3)(2)=3
x2=42=(2)
⋅(2)(2)=2
