(2x+6)(5x-1) Foil method

1 answer:

8 0

Multiple 2x * 5x =10x^2
Multiple 2x * -1 = -2x
Multiple 6 * 5x = 30x
Multiple 6 * -1 = -6
Add 30x + (-2x) = -28x
10x^2 + 28x -6 is the final answer

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The Venn diagram shows all of the elements in sets A, B and ξ. Find the elements in (A ∩ B) U (A U B)’

marusya05 [52]

This is impossible to answer without knowing what the sets A and B contain (and what ξ even refers to - universal set?).

However, we have

(A U B)' = A' ∩ B'

so that

(A ∩ B) U (A U B)' = (A ∩ B) U (A' ∩ B') = (A U A') ∩ (B U B')

If ξ is indeed the universal set, then both A U A' = ξ and B U B' = ξ, so we end up with ξ ∩ ξ = ξ.

8 0

3 years ago

Suppose integral [4th root(1/cos^2x - 1)]/sin(2x) dx = A<br>What is the value of the A^2?<br><br>

Alla [95]

$\large \mathbb{PROBLEM:}$

$\begin{array}{l} \textsf{Suppose }\displaystyle \sf \int \dfrac{\sqrt[4]{\frac{1}{\cos^2 x} - 1}}{\sin 2x}\ dx = A \\ \\ \textsf{What is the value of }\sf A^2? \end{array}$

$\large \mathbb{SOLUTION:}$

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