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

What is the inverse of the function f(x) = one-ninth * x + 2?
The perimeter of a triangle is 6p2-4p+9 and two of its adjacent side are p2 -2p+1 and 3p2-5p+3.Find the 3rd side
write a short note on remains of Indus valley civilization found at Dholavira.​
Is anyone else a libra
Kai saved all she earned each month and put it into a savings account. The amount she had in her savings account is recorded below. What equation best represent
Which ordered pair is a solution of the equation? y = -2x + 5
Part D Explain how your model is different from the model in the picture.
For the reaction represented by the equation 2h+O2– 2H2O, how may grams of water are produced from 6.00 mol of hydrogen? Atomic mass of hyorogen = 1.0gmol Atomi
If temperature is 4 degrees and falls by 6 degrees, what is the new temperature?
slope for (6,5) (14, -3)