Question

How many real roots does it have?
\(2x^5+8x-7\)
A) 0
B) 1
C)2
D) 3
E)5
Please, help

Answer 1

@zepdrix

Answer 2

Let f(x) = 2x^5 +8x -7
f'(x) = 10x^4 +8 >0 for all x, hence f(x) monotonous increasing
f(0) = -7
f(1) = 3
hence only 1 root
Am I wrong?