1. Find the product $(x - 3)(2x^2 + 5x - 7).$
2. Find the coefficient of $z$ in the product\[(-3z^2 - 7z + 4)(6z^2 - z + 6).\]
3. Let $f(x) = x^4-3x^2 + 2$ and $g(x) = 2x^4 - 6x^2 + 2x -1$. Let $b$ be a constant. What is the smallest possible degree of the polynomial $f(x) + b\cdot g(x)$?
4. Let $f(x) = x^4-3x^2 + 2$ and $g(x) = 2x^4 - 6x^2 + 2x -1$. What is the degree of $f(x) \cdot g(x)$?
please help quick! Thanks!
1. \((x-3)(2x^2 + 5x - 7) = (2x^3 + 5x^2 - 7x) -(6x^2 - 15x + 21)\)
\(\boxed{2x^3 - x^2 + 8x - 21}\)
2. \((-3z^2 - 7z + 4)(6z^2 - z + 6) = -18z^4 - 39z^3 + 13z^2 -\boxed{ 46z} + 24\)
The coefficient of z is -46.
3. f(x) has degree 4 and g(x) has degree 4. Because b is a constant, the maximum degree of \(f(x) + b\cdot g(x)\) can only be 4.
4. f(x) has degree 4 and g(x) has degree 4. By multiplying, you are adding the degrees, so the degree of f(x) * g(x) is 8.
Hi Cubey,
Welcome to the Web2.0 forum!
I know you are very active here and I like your enthusiasm
but
Please do not answer multiple questions on a single post and please try not to give full answers.
Hints and partial answers (for which you know the full answer) are much better.
This is especially true when it is clear the asker is just looking for quick answers.
I am sure you do not want this forum to be a place where people come with the sole intention of cheating.