Algebra - Polynomials | Practice Hub

Give the coefficient of $x^{4}$ in the binomial expansion of $\left (6x+ \frac{1}{6}\right )^{7}$ .

$\frac{35}{6}$

Explanation

If the expression $\left ( A x + B\right )^{n}$ is expanded, then by the binomial theorem, the $x^{k}$ term is

$C(n, k) \cdot\left ( Ax \right )^{k} \cdot B ^{n - k}$

$= C(n, k) \cdot A ^{k} \cdot B ^{n - k} \cdot x^{k}$

or, equivalently, the coefficient of $x^{k}$ is

$C(n, k) \cdot A ^{k} \cdot B ^{n - k}$

Therefore, the $x^{4}$ coefficient can be determined by setting

$A = 6, B = \frac{1}{6}, n = 7, k= 4$ :

$C(7,4) \cdot 6 ^{4} \cdot\left ( \frac{1}{6} \right ) ^{7-4}$

$=C(7,4) \cdot 6 ^{4} \cdot\left ( \frac{1}{6} \right ) ^{3}$

$=35 \cdot 1,296 \cdot \frac{1}{216}$

Give the coefficient of $x^{2}$ in the product

$\left ( x+ 0.4\right ) (x - 0.2) (3x-0.7)$ .

Explanation

While this problem can be answered by multiplying the three binomials, it is not necessary. There are three ways to multiply one term from each binomial such that two terms and one constant are multiplied; find the three products and add them, as follows:

$\left (\underline{ x}+ 0.4\right ) (\underline{x} - 0.2) (3x\underline{-0.7})$

$x \cdot x \cdot (-0.7) = -0.7x^{2}$

$\left (\underline{ x}+ 0.4\right ) (x \underline{-0.2})(\underline{3x}-0.7)$

$x \cdot (-0.2) \cdot 3x= -0.6x^{2}$

$\left (x+ \underline{0.4}\right ) (\underline{x} - 0.2)(\underline{3x}-0.7)$

$0.4 \cdot x \cdot 3x = 1.2 x^{2}$

Add: $-0.7x^{2}+ (-0.6x^{2})+ 1.2x^{2} = -0.1x^{2}$ .

The correct response is .

Give the coefficient of $x^{5}$ in the binomial expansion of $\left ( 2x+ 0.5\right )^{8}$ .

Explanation

If the expression $\left ( A x + B\right )^{n}$ is expanded, then by the binomial theorem, the $x^{k}$ term is

$C(n, k) \cdot\left ( Ax \right )^{k} \cdot B ^{n - k}$

$= C(n, k) \cdot A ^{k} \cdot B ^{n - k} \cdot x^{k}$

or, equivalently, the coefficient of $x^{k}$ is

$C(n, k) \cdot A ^{k} \cdot B ^{n - k}$

Therefore, the $x^{5}$ coefficient can be determined by setting

$C(8,5) \cdot 2^{5} \cdot 0.5 ^{8-5}$

$=C(8,5) \cdot 2^{5} \cdot 0.5 ^{3}$

$= 56\cdot 32 \cdot 0.125$

Expand:

$3x^{2}-25x-18$

$3x^{2}-29x-18$

$3x^{2}-18x-29$

$3x^{2}-18x-25$

None of the other answers

Explanation

To multiple these binomials, you can use the FOIL method to multiply each of the expressions individually.This will give you

or $3x^{2}-25x-18$ .

What is the degree of the following polynomial?

Explanation

To find the degree of a polynomial, simply find the highest exponent in the expression. As seven is the highest exponent above, it is also the degree of the polynomial.

What is the degree of the following polynomial?

Explanation

To find the degree of a polynomial, simply find the highest exponent in the expression. As eight is the highest exponent above, it is also the degree of the polynomial.

Find the degree of the following polynomial:

Explanation

Find the degree of the following polynomial:

To find the degree of a polynomial, we simply need to look at its highest exponent.

The degree will be equal to the highest exponent, which in this case, is 7

$g(x)=6x^{\color{DarkGreen} 7}-5x^5+144x^3-1200x+33$

So, the correct answer is 7

Find the degree of the following polynomial:

Explanation

This problem is asking us to solve for the degree of the polynomial. This merely means "what is the greatest exponent in the expression?" It's important to keep in mind that coefficients do not matter because they do not affect exponents.

In order to easily see what the greatest exponent is, it is best to rearrange the terms in descending order with respect to their exponents.

Now we can see that 5 is the greatest exponent. Therefore, the degree of the polynomial is 5.

What is the degree of the following polynomial?

Explanation

To find the degree of a polynomial, simply find the highest exponent in the expression. As five is the highest exponent above, it is also the degree of the polynomial.

Which of these equations is a third-degree polynomial?