SOLUTION: Please help me solve this problem: f(t) = 2 t squared - 4t -1 find f(2) and then f(-1)

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Question 121084: Please help me solve this problem: f(t) = 2 t squared - 4t -1 find f(2) and then f(-1)
Found 2 solutions by solver91311, praseenakos@yahoo.com:
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!
if f%28t%29=2t%5E2-4t-1 then f%28a%29=2a%5E2-4a-1.

So f%282%29=2%282%29%5E2-4%282%29-1
f%282%29=8-8-1
f%282%29=-1.

Do the other one the same way, but remember to pay attention to your signs.

Answer by praseenakos@yahoo.com(507) About Me  (Show Source):
You can put this solution on YOUR website!
Question:
f(t) = 2 t squared - 4t -1 find f(2) and then f(-1)
Answer
f%28t%29+=+2%28t%29%5E2+-+4t+-1

To find f(2), replace t by 2 in the given function.....

==>f%282%29+=+2%282%29%5E2+-+4%282%29-1


==>f%282%29+=+2%2A4+-+4%282%29-1


==>f%282%29+=+8-+8+-1

==>f%282%29+=+-1




To find, f(-1), replace t by (-1)in the given function.....


==>f%28-1%29+=+2%28-1%29%5E2+-+4%28-1%29-1


==>f%28-1%29+=+2%2A1+-+4%28-1%29-1



==>f%28-1%29+=+2+%2B4-1


==>f%28-1%29+=+5+

Hope you found the explanation useful.

Regards.

Praseena.