Find the value of each given polynomial at the given value of its variable : (i) 5x2–7x+2 at x = 2 (ii) x2+15x–4 at x = -3 (iii) 3y+8–2y2 at y = –3 (v) x2+3x+1 at x = -1/3 (v) x3–3x2+5x+2 at x = – 1