Cos xcos y=1/2(sin(x+y)+ sin(x-y))

Mathematics

1 answer:

garri49 [273]3 years ago

7 0

Taking Rhs

1/2 [sin(x+y)+ sin (x-y)]

using sinA + sin B = 2 cos (A+B)/2 cos( A - B)/2

1/2 [ 2 Cos ( x+y+x-y)/2 . Cos (x+y-x+y)/2]

=Cos 2x/2. Cos 2y/2 = Cos x . Cos y

Hence true

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Step-by-step explanation:

We are told that:

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So, Scott served X orders.

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We will have then:

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3 years ago

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Vika [28.1K]

The formula:
A = bh + L (s1 + s2 + s3)

A: area
b: base
h: height
L: length
s1: side 1 (cross-sectional area)
s2: side 2 (cross-sectional area)
s3: side 3 (cross-sectional area)

Here’s an example (see attached image)

A = (4 x 6) + (12 x [7 + 7 + 4])
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I hope this helped? Comment if you need more explanation or anything!