Question

I need help on theses 3 problems.
If p(x) = 3x^2 - 2x + 5 and r(x) = x^3 + x + 1, find each value.
30. r(3a)
31. 4p(a)
32. p(a^2)

Answer 1

REALLY BIG Hint: p(Frog) = 3(Frog)^2 - 2(Frog) + 5

Answer 2

that really doesn't help me

Answer 3

\[r(\spadesuit)=\spadesuit ^3+\spadesuit +1\]
replace \(\spadesuit\) by \(3a\)

Answer 4

@Firejay5 I will give you a small hint :

if P(x) = x^2 - 3

then P(1) = 1^2 - 3 = 1 - 3 = -2

Answer 5

\[r(3a)=(3a)^3+(3a)+1\]

Answer 6

lol @satellite73 nice :)

Answer 7

actually i liked "frog" better, just couldn't figure out how to make one in latex

Answer 8

so is (3a)^3 + (3a) + 1 is the answer

Answer 9

yes, unless you want to change it to
\[27a^3+3a+1\]

Answer 10

what answer does that belong to

Answer 11

\(r(3a)\)

Answer 12

This is a problem in understanding the notation.

When you define a function, f(x) = 3x - 5, the terminology f(a) means to substitute the value 'a' everywhere 'x' appears in the definition.

f(x) = 3x-5
f(2) = 3(2) - 5
f(2a) = 3(2a) - 5
f(f(x)) = 3(f(x)) - 5
f(Pittsburgh) = 3(Pittsburgh) - 5
f(You must get this idea stuck in your head) = 3(You must get this idea stuck in your head) - 5

Now, let's see your results.

Answer 13

\[p(x) = 3x^2 - 2x +5 \] means fill in the \(\Box\)
\[p(x) = 3\Box^2 - 2\Box +5\]

Answer 14

which answer is the correct answer

Answer 15

they are the same, since \((3a)^3=27a^3\)

Answer 16

@satellite73 what about 32 and then I am done, because I don't get it either

Answer 17

@Hero Yes???