bikram57
bikram57 bikram57
  • 02-07-2021
  • Mathematics
contestada

if cosA=3√2/5,then show that cos2A=11/25

Respuesta :

devishri1977
devishri1977 devishri1977
  • 02-07-2021

Answer:

Step-by-step explanation:

Cos 2A = 2Cos² A - 1

             [tex]= 2*(\frac{3\sqrt{2}}{5})^{2}-1\\\\=2*(\frac{3^{2}*(\sqrt{2})^{2}}{5^{2}})-1\\\\=2*\frac{9*2}{25} - 1\\\\=\frac{36}{25}-1\\\\=\frac{36}{25}-\frac{25}{25}\\\\=\frac{11}{25}[/tex]

Answer Link

Otras preguntas

Which Portuguese nobleman led a fleet of 13 ships on a voyage to India but first sailed west to use the winds? A. Vasco de Gama B. Prince Henry the Navigator
why might a volcanic eruption lead to cooler temperatures over a large area around the volcano
What is 25 divided by 1280
A person perception of the world is known a a regional map
Explain how the presence of coal-fired electricity plants can affect the ability of lakes to support life?
340 pages 20% decrease
Which equation matches the sentence? Column A Column B 1. Seven more than 2 times a number is 23. 2. The difference of 2 times a number and 7 is 23. 3. The sum
Find the reciprocal of the number. Multiply to check your answer. HELP 1  1/2 A. 3/2 B. 2/3 C. 2/11 D. 11/2
Who rescues the narrator from his prison, on the story "The Pit and the Pendulum?
Im so hopeless no one can answer my homework question and its due tommorow :( How much pressure is exerted when air is being compressed?