Answer:
Part A
a·(a² - a + 1) + 5·a = a³ - a² + 6·a
Part B
The value of a·(a² - a + 1) + 5·a, for a = -2 is -24
Step-by-step explanation:
Part A
The given function is a·(a² - a + 1) + 5·a
The function is simplified by expanding the product of sums into sums of products, as follows;
a·(a² - a + 1) + 5·a = a × a² - a × a + a × 1 + 5·a = a³ - a² + a + 5·a = a³ - a² + 6·a
The function, a·(a² - a + 1) + 5·a, in simplified format is therefore;
a·(a² - a + 1) + 5·a = a³ - a² + 6·a
Part B
When a = -2, we get;
(a³ - a² + 6·a)
= (-2)³ - (-2)² + 6·(-2) = -8 - 4 - 12 = -24
Answer:
1125.4 Hz
Step-by-step explanation:
The resonant frequency is the frequency at with the inductive reactance is equal to the capacitive reactance. It is given by the relation ...

where L is in henries, and C is in farads.
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For the given circuit values, the resonant frequency is ...

The resonant frequency of this circuit is about 1125.4 hertz.
A (15.4-8.1=7.3) has two significant figure so A is the ANSWER
while the all other options has 3 significant figure