Question

r = 1 is a root of 4x^2 – 3x – 1 = 0

^ this false?

r = -1 is a root of 4x^2 – 3x – 1 = 0


^ it is true?

Answer 1

substitute -1 into x of 4x^2 - 3x - 1

\[\implies 4(-1) ^2 - 3(-1) - 1 \implies 4(1) + 3 - 1 \implies 4 + 3 - 1 \implies 6\]
therefore r = -1 is NOT a root

if it's a root..the result should be 0

Answer 2

does that help?

Answer 3

Yes

Answer 4

the first came as true for me?

Answer 5

you mean r = 1?

Answer 6

yeah

Answer 7

yes it's a root becuase

4(1)^2 - 3(1) - 1 = 4 - 3 - 1 = 4 - 4 = 0