The function f is defined by f(x) = 2x³ + 3x² + cx + 8, where c is a constant. In the xy-plane, the graph of f intersects the x-axis at the three points (−4, 0), (1/2, 0), and (p, 0). What is the value of c?
-18
-2
2
10
3 answers
10
ok, the bot is wrong,
using (−4, 0)
f(-4) = 2(-4)³ + 3(-4)² + c(-4) + 8 = 0
= -128 + 48 - 4c + 8
= 0
then c = -18
and f(x) = 2x³ + 3x² - 18x + 8
check for f(1/2) = 0
2(1/8) + 3(1/4) - 18(1/2) + 8 = 0
c = -18
don't know what p has to do with the question.
using (−4, 0)
f(-4) = 2(-4)³ + 3(-4)² + c(-4) + 8 = 0
= -128 + 48 - 4c + 8
= 0
then c = -18
and f(x) = 2x³ + 3x² - 18x + 8
check for f(1/2) = 0
2(1/8) + 3(1/4) - 18(1/2) + 8 = 0
c = -18
don't know what p has to do with the question.
thank you smm