How do you find the exact value of $cos70sin48-cos48sin70$ using the sum and difference, double angle or half angle formulas?

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Answer 1 · 2018-04-15T04:28:18

$sin(-22) = -sin22$

From the equation, you can tell that it is $sin(a-b)$

$sin(a-b) = cosbsina-cosasinb$

When comparing with the equation, we can say that $a=48, b=70$

$sin(a-b) = sin (48-70)$ = $sin(-22) = -sin(22)$

How do you find the exact value of cos70sin48-cos48sin70cos70sin48-cos48sin70 using the sum and difference, double angle or half angle formulas?