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Given that tan theta =-3/4, 0°<theta 90°. find cos theta + sin theta.



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Answer: cosθ + sinθ = -1/4.

Step-by-step explanation:

cos theta + sin theta = -√(3^2 - 4^2) / 4 = -1/4

The given equation is tanθ = -3/4. We can use the Pythagorean identity to find cosθ and sinθ, which states that cos²θ + sin²θ = 1.

Since we know that tanθ = -3/4, we can substitute this value into the Pythagorean identity to get:

cos²θ + (-3/4)² = 1

Solving for cosθ gives us cosθ = √(3² - 4²) / 4 = -1/4.

Similarly, we can solve for sinθ to get sinθ = -3/4.

Now, we can add cosθ and sinθ together to get cosθ + sinθ = -1/4.

User Arun Tom
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