Prove this identify :
2 cos^2 (45°-A ) = 1 +sin 2 A ​

I am guessing that you mean 2cos2(45° - A) = 1 + sin2A

According to a double angle identity, 2cos2θ - 1 = cos(2θ)

So, 2cos2(45° - A) - 1

= cos (90° - 2A) =cos90°cos2A + sin90°sin2A = (0)cos2A + (1)sin2A = sin2

Thus, 2cos2(45° -A ) = 1 + sin2A

the answer is d

the answer is in the first quadrant, which make the y-int positive.

since the dots are going down, therefore the correlation is negative

i hope it is right.

maximum area = xy = (16)(32) = 512 ft2

to maximize the area of the garden, the side of the fence parallel to the side of the house should be 32 ft long, and the other two sides should both have length 16 ft.'

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