Skip to main content
A

Anonymous

Dec 22, 2024

Tan theta=4/3 ….piNovember 17, 2021 by thanh

I need assistance in finding the exact values for cos(θ/2) and sin(θ/2), given that tan(θ) = 4/3. Thank you!

1 Answers

A
Anonymous

Jan 27, 2025

tan(θ) = 4/3

π < θ < 3π/2, θ is in QIII. To find cos(θ/2) and sin(θ/2), you only need to now where θ/2 is located (to know the signs of cos(θ/2) and sin(θ/2)) and you need to know cos(θ). Since θ/2 is in QIII, π < θ < 3π/2, π/2 < θ/2 < 3π/4 and θ/2 is in QII.

cos(θ/2) = ±√((1 – cos(θ))/2)

sin(θ/2) = ±√((1 + cos(θ))/2)

cos(θ) = -3/5 since tan(θ) = 4/3 in QIII.

Since θ/2 is in QII cos(θ/2) is negative and sin(θ/2) is positive.

cos(θ/2) = -√((1 – -3/5)/2)

sin(θ/2) = √((1 + -3/5))/2)

cos(θ/2) = -√((1 + 3/5)/2) —–> cos(θ/2) = -√((8/5)/2) —–> cos(θ/2) = -√(8/10) —–> cos(θ/2) = -2/√5 —–> cos(θ/2) = -2√5/5

sin(θ/2) = √((1 – 3/5))/2) —–> sin(θ/2) = √((2/5))/2 —–> sin(θ/2) = √(2/10) —–> sin(θ/2) = √(1/5) —-> sin(θ/2) = √5/5

Want to answer this question?

Join our community to share your knowledge!

Related Questions

3
Another expression for “it is raining” is “Está nublado.”

Question 1 (Yes/No Worth 1 point): Another expression for "it is raining" is "Está nublado." (Yes/No) Question 3 (Fill-i...

3
Find the circumference of p. leave your answer in terms of pi. the radious is 5 in.

Find the circumference of a circle with a radius of 5 inches. Please express your answer in terms of pi.

1
Guys help please!! Just 1 Algebra 2 question?

I need assistance with an Algebra 2 problem. The question states that the variable ( r ) varies directly with ( s ) and...

2
how is Frank Garza’s Jockey School?

I hope this message finds you well. I have a few questions regarding Frank Garza’s Jockey School. I want to clarify that...

3
how tall is 77 inches in feet?

How tall is 77 inches when converted to feet?

8
I am in 12th……I hav my physics board exam tomorrow……how do I complete my full course in one day ?

I'm in 12th grade, and I have my physics board exam tomorrow. How can I effectively cover the entire course material in...

3
In circle O, ST is a diameter. What must be the value of x?

In circle O, ST is a diameter. What is the value of x if (2x + 8) equals one of the following options: 22.0, 25.0, 25.4,...

6
projectile motion homework?

A rescue pilot needs to drop a survival kit while flying at an altitude of 2,000.0 meters with a forward velocity of 100...

10
Preschool vs. Montessori?

Hi everyone, I’m trying to make a decision between enrolling my child in a preschool or a Montessori program. He’s curr...

3
what is the hybridization of phosphorus atom in PCl3?

What is the hybridization of the phosphorus atom in PCl3? Additionally, could you please provide an explanation of the s...