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

Is the function below even, odd, or neither? Determine its axis of symmetry (x-axis, y-axis, origin, or none). Is it a one-to-one function?
Identify the sentence that uses a semicolon correctly. Caring for a dog helps build empathy, in fact; research has shown a empathy scores. On average, dog owner
do you let your kids jump or do flips on hotel beds?
What role did the silk road play in generating an interrelated trade network? (include an introduction paragraph, thesis, and one supporting paragraph)
simplify -4(x+1)+3x and then evaluate when x=1
Find the measure of angle b.​
DUE IN 20 MINUITES! Consider the interval containing Point A (4,-4) and Point B (5,-7) _ Find the rise (change in the y-value) going from point A to point B.
Is the discriminant positive, negative, or 0 for each graph below? Explain your choices in one or two sentences for each graph.
Answer number 9 or 10 or 8
Like all Romantic writers, Blake manages to draw a connection between man, nature, and the truth with which he himself _____. is ignoring is wrestling has maste