Answer:
The correct prove will be:

Step-by-step explanation:

Multiply and Divide by 
= 
⇒ Let
= Ф and 7Ф = 
= sin2Ф sin3Ф sin5Ф ÷ 2cosФ
= 1/2(2sin2Фsin5Ф)sin3Ф ÷ 2cosФ
= (cos3Ф - cos7Ф) sin3Ф ÷ 4cosФ
= 1/2(2cos3Ф sin3Ф) ÷ 4cosФ ∵cos7Ф = 0
= sin6Ф ÷ 8cosФ
= sin(7Ф - Ф) ÷ 8cosФ
= (sin7ФcosФ - cos7ФsinФ) ÷ 8cosФ ∵sin7Ф = 1
= cosФ ÷ 8cosФ
= 1/8
Hence, The correct prove will be:

Keywords: prove, sinФ, cosФ
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Answer:
±6i√2
Step-by-step explanation:
Recall that the square root of a negative number is imaginary, which is shown by the use of "i."
Examples: √4 = ±2; √4 = i√4 = ±i2
Then √72 = ±√36√2 = ±6√2, and
√(-72) = ± i√36√2 = ±6i√2
Note that this is identical to the result shown in the problem: √(36·2·(-1) )
Similar triangles have corresponding sides with proportional lengths.
AB/BC = DE/EF
5/9 = 7.5/EF
5(EF) = 9 * 7.5
5(EF) = 67.5
EF = 13.5
Answer:
the first choice! A struggle between and individual and another person
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