Simplify and express the result as a rational number in each case :
` (-3) xx ( -3)^(4)`

Answer

To simplify the expression \((-3) \times (-3)^4\), we can follow these steps:

### Step 1: Identify the base and the exponents
The expression consists of a base of \(-3\) and an exponent of \(4\). We can rewrite \((-3)\) as \((-3)^1\) to make the bases the same.

### Step 2: Rewrite the expression
Now we can rewrite the expression as:
\[ (-3)^1 \times (-3)^4 \]

### Step 3: Apply the exponent rule
According to the exponent rule, when multiplying like bases, we add the exponents:
\[ (-3)^{1 + 4} = (-3)^5 \]

### Step 4: Calculate \((-3)^5\)
Now we need to calculate \((-3)^5\):
\[ (-3)^5 = -3 \times -3 \times -3 \times -3 \times -3 \]
Calculating step-by-step:
- \(-3 \times -3 = 9\)
- \(9 \times -3 = -27\)
- \(-27 \times -3 = 81\)
- \(81 \times -3 = -243\)

So, \((-3)^5 = -243\).

### Final Answer
Thus, the simplified expression is:
\[ \boxed{-243} \]

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