Question

x a quarta-5x ao quadrado +4=0​

Answer 1

x⁴-5x²+4=0

X⁴-5x²+25/4-25/4+4=0 ×(4)

4x⁴-20x²+25-25+16=0

4x⁴-20x²+25=25-16

4x⁴-20x²+25=9

(2x²-5)²=9

2x²-5=±√9

2x²-5=±3

2x²-5=3

2x²=3+5

2x²=8

x²=8/2

x²=4

x=±4

x=±2

2x²-5=-3

2x²=5-3

2x²=2

x²=2/2

x²=1

x=±√1

x=±1

S={-2,-1,1,2}