Question 636736
  <pre><font face = "Tohoma" size = 3 color = "indigo"><b> 
Hi,
Assume You meant:
f(x)= 3x^3+5x - 5 ;[-1,0]
f(-1) = -13,   f(0) = -5,  both < 0
NO, f(x) does not have a zero in that interval
{{{drawing(300,300,   -6, 6, -15, 6, grid(1),
graph( 300, 300, -6, 6, -15, 6,0, 3x^3+5x - 5))}}}