Help with proving identities questions please (1 Viewer)

InteGrand

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Can anyone please help me solve this proof, its from the cambridge 3 unit prelim textbook.

Thanks, ive attached the question.
For the first one, multiply top and bottom of the LHS by tan(x). This makes the numerator become tan(x) + 1, and the denominator is tan(x)(1 + tan(x)), so the fraction becomes 1/(tan(x)) = cot(x).

For the second one, multiply top and bottom of the LHS by 1 – sin(α), and remember the difference of two squares and that 1 – sin2(α) = cos2(α).
 

leehuan

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First step: Multiply top and bottom by tan(x)
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dabatman

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For the first one, multiply top and bottom of the LHS by tan(x). This makes the numerator become tan(x) + 1, and the denominator is tan(x)(1 + tan(x)), so the fraction becomes 1/(tan(x)) = cot(x).

For the second one, multiply top and bottom of the LHS by 1 – sin(α), and remember the difference of two squares and that 1 – sin2(α) = cos2(α).
Thanks
 

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