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given angles A and B are in quadrant 1 with tan A = 2/3 and sin B = square root 5/5 find tan(a+b) showing all steps

User Chezhian
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Answer: We can start by using the trigonometric identity:

tan(A + B) = (tan A + tan B) / (1 - tan A * tan B)

To find tan A and tan B, we can use the given information:

tan A = 2/3

sin B = sqrt(5)/5

To find tan B, we can use the relationship between sin, cos and tan:

tan B = sin B / cos B

Since sin² B + cos² B = 1, we know that:

cos B = sqrt(1 - sin² B) = sqrt(1 - (5/5)²) = sqrt(1 - (5/25)) = sqrt(20/25) = 2/sqrt(5)

So,

tan B = sin B / cos B = sqrt(5)/5 / 2/sqrt(5) = sqrt(5) / (2*sqrt(5)) = sqrt(5) / 10

Now, we can substitute these values back into the original identity:

tan(A + B) = (2/3 + sqrt(5)/10) / (1 - (2/3)(sqrt(5)/10))

Simplifying this expression gives us:

tan(A + B) = (2/3 + sqrt(5)/10) / (7/15)

And that's the final answer.

Explanation:

User David Campos
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