Question

In Problems 1 and 2, use a graphing utility to approximate the solutions of each equation rounded to two decimal places. All solutions lie between -10 and 10.

1. -x^3+3x+1=0

2. -x^4+7= x^2-2

Answer 1

yes

Answer 2

no they need to be answered

@KlOwNlOvE help me out I posted in the wrong section lol

Answer 3

for 2. subtract x^2-2 from both sides
-x^4+7-(x^2-2)
distribute the negative
-x^4-x^2+9
rewrite the equation in u=x^2 u^2=x^4
-u^2-u+9=0
divide both sides by -1
u^2+u-9=0
add 9 to both sides
u^2+u=9
add (1/2)^2 to both sides
u^2+u+1/4=37/4
complete the left hand side to square using the identity x^2+2ax+a^2=(x+a)^2
\[(u+\frac{ 1 }{ 4 })^{2}=\frac{ 37 }{ 4 }\]
\[u+\frac{ 1 }{ 4 }=\sqrt{\frac{ 37 }{ 4 }}\]
now subtract the 1/4 from both sides
\[u=\frac{ \sqrt{37}-1 }{ 2 }\]

Answer 4

@SolomonZelman seem right?