Question 1031121
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sen(a)= 3/5, &#960;/2 < a < &#960; and cos (B)=20/29, 0 < B <&#960;/2, sin (a-B)= ????
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<pre>
Use the formula  sin(a - b) = sin(a)*cos(b) - cos(a)*sin(b).
   (Regarding this formula, see the lesson <A HREF=https://www.algebra.com/algebra/homework/Trigonometry-basics/Addition-and-subtraction-formulas.lesson>Addition and subtraction formulas</A> in this site.)


You need to know cos(a) and sin(b) in addition to the given sin(a) and cos(b).


Calculate

cos(a) = +/- {{{sqrt(1-sin^2(a))}}}. Choose correct sign before  sqrt  based on info about angle "a".

sin(b) = +/- {{{sqrt(1-cos^2(b))}}}. Choose correct sign before  sqrt  based on info about angle "b".

See the sample in the lesson <A HREF=https://www.algebra.com/algebra/homework/Trigonometry-basics/Calculating-trigonometric-functions-of-angles.lesson>Calculating trigonometric functions of angles></A>,  Problem 3.
</pre>

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I was not able to read your original formula, and therefore corrected it by inserting the blank dividers.