Use trigonometric identities to solve each equation within the given domain. If you can explain it that would be best, I want to know how to actually do it. Thanks!

it happens during combustion and impacts the environment because the plants and trees take in that and it can cause them to die.

for ex: the reciprocal of 3/4 is 4/3. it is the opposite.

reciprocal definition:

a mathematical expression or function so related to another that their product is one; the quantity obtained by dividing the number one by a given quantity.

answer for #1 is c

answer for #2 is d

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