The greatest slope along the graph represented by the equation 4x2−y2+2y−1=0, is-
4x²-y²+2y-1 = 0
⇒ 4x²-(y²-2y+1) = 0
⇒ 4x²-(y-1)² = 0
⇒ 4x² = (y-1)²
Taking square root,
This has the following two solutions:
y = -2x+1, with slope -2
y = 2x+1, with slope 2
Thus, greatest slope is 2.