1. **Problem Statement:**
Find the number that must be added to the polynomial $$2x^3 - 7x^2 + 2x$$ so that when the resulting polynomial is divided by $$2x - 3$$, the remainder is $$-2$$.
2. **Formula and Important Rule:**
By the Remainder Theorem, the remainder when a polynomial $$f(x)$$ is divided by a linear divisor $$ax - b$$ is $$f\left(\frac{b}{a}\right)$$.
3. **Apply the Remainder Theorem:**
Here, divisor is $$2x - 3$$, so $$a=2$$ and $$b=3$$.
The remainder when dividing by $$2x - 3$$ is $$f\left(\frac{3}{2}\right)$$.
4. **Evaluate the original polynomial at $$x=\frac{3}{2}$$:**
$$f\left(\frac{3}{2}\right) = 2\left(\frac{3}{2}\right)^3 - 7\left(\frac{3}{2}\right)^2 + 2\left(\frac{3}{2}\right)$$
Calculate each term:
- $$\left(\frac{3}{2}\right)^3 = \frac{27}{8}$$
- $$\left(\frac{3}{2}\right)^2 = \frac{9}{4}$$
So,
$$f\left(\frac{3}{2}\right) = 2 \times \frac{27}{8} - 7 \times \frac{9}{4} + 2 \times \frac{3}{2} = \frac{54}{8} - \frac{63}{4} + 3$$
Simplify fractions:
- $$\frac{54}{8} = \frac{27}{4}$$
- $$\frac{63}{4}$$ stays as is
So,
$$f\left(\frac{3}{2}\right) = \frac{27}{4} - \frac{63}{4} + 3 = -\frac{36}{4} + 3 = -9 + 3 = -6$$
5. **Let the number to be added be $$k$$.**
Then the new polynomial is $$2x^3 - 7x^2 + 2x + k$$.
The remainder when divided by $$2x - 3$$ is:
$$f\left(\frac{3}{2}\right) + k = -6 + k$$
6. **Set the remainder equal to $$-2$$ and solve for $$k$$:**
$$-6 + k = -2$$
$$k = -2 + 6 = 4$$
**Final answer:** The number to be added is **4**.
Polynomial Remainder Ed9A00
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