➷ Just work with what is inside the parenthesis
Also, move around the terms to help it make more sense:
(cosA cosB - cosA cosB + sinA sinB + sinA sinB)
As you can see, the 'cosA cosB' would cancel out through subtraction.
Now we have this:
(sinA sinB + sinA sinB)
This is just two sets of sinA sinB so it can be written as:
(2 * sinA sinB)
Simply place the values outside the parenthesis back there to get the answer
SinA sinB = 1/2 * (2 * sinA sinB)
➶ Hope This Helps You!
➶ Good Luck (:
➶ Have A Great Day ^-^
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