OasisDevkota OasisDevkota
  • 23-12-2020
  • Mathematics
contestada

prove that:
[tex] {sin}^{2} \: \frac{7\pi}{8} + \: {sin}^{2} \: \frac{5\pi}{8} = 1 [/tex]
​

prove thattex sin2 frac7pi8 sin2 frac5pi8 1 tex class=

Respuesta :

LammettHash
LammettHash LammettHash
  • 01-01-2021

Recall that

sin²(x) = (1 - cos(2x))/2

so that

sin²(7π/8) = (1 - cos(7π/4))/2

sin²(5π/8) = (1 - cos(5π/4))/2

Then

sin²(7π/8) + sin²(5π/8) = (1 - cos(7π/4) + 1 - cos(5π/4))/2

… = 1 - 1/2 (cos(7π/4) + cos(5π/4))

… = 1 - 1/2 (1/√2 - 1/√2)

… = 1

Answer Link

Otras preguntas

The polynomial 16x + 2 is a
list and briefly describe five ways humans are impacting the environment please I need help this is my last hope
What is science fiction?
A students claims that 8 to the 3rd power and 8 to the negative 5th power is greater than 1. Explain whether the student is correct or not.
Which U.S. territory or protectorate is located in the Caribbean Sea? American Samoa Guam Howland Island Puerto Rico
There are 25 students in a class. Sixteen of those students are boys. What percent of the class are girls? The percent of girls in the class is %
Velocity may be expressed in which I f the following units?
Short vowel of accomplice
what morphology is represented in the picture
Which one of the following improved human relations skills will allow you to more willingly take on challenging subjects? A. Self Confidence B. Communication