Verify the following Identity-

Mathematics

1 answer:

Olenka [21]3 years ago

4 0

We know that
sin(A + B) = sin A cos B + cos A sin B----> equation 1
sin(A − B) = sin A cos B − cos A sin<span> B----> equation 2
so
</span>tan A+tan B=[sin A/cos A]+[sin B/cos B]
=[(cos B*sin A)+(sin B*cos A)](cos A*cos B)
substitute equation 1
sin (A+B)/(cos A*cos B)

tan A-tan B=[sin A/cos A]-[sin B/cos B]
=[(cos B*sin A)-(sin B*cos A)](cos A*cos B)
substitute equation 2
sin (A-B)/(cos A*cos B)

[tan A+tan B]/[tan A-tan B]
=[sin (A+B)/(cos A*cos B)]/[sin (A-B)/(cos A*cos B)]
=[sin (A+B)/sin (A-B)]

hence
[tan A+tan B]/[tan A-tan B]=[sin (A+B)/sin (A-B)]

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Find the difference between the fastest girls time and the slowest girl time. Barbra ran 3 3/10, Donna ran 2 4/5 , Cindy ran 4 3

Xelga [282]

Answer: 2.5 or 2 1/2

Step-by-step explanation:

You can convert the mixed fractions to decimal numbers:

- Divide the numerator by the denominator of the fraction.

- Add the result to the whole number.

Thenyou have:

Barbara's time: $3\ 3/10=3+0.3=3.3$