The value of cos(π/5)cos(2π/5)cos(4π/5)cos(8π/5) - Sarthaks eConnect | Largest Online Education Community
![Show that the roots of the equation 16x^4 - 20x^2 + 5= 0 are cos((kx)/10) for k = 1,3,7 and 9 And Deduce that cos^2(pi/10)cos^2((3pi)/10) = 5/16? | Socratic Show that the roots of the equation 16x^4 - 20x^2 + 5= 0 are cos((kx)/10) for k = 1,3,7 and 9 And Deduce that cos^2(pi/10)cos^2((3pi)/10) = 5/16? | Socratic](https://useruploads.socratic.org/wrrVIwDQlqpWkqqEpdyz_mat1.jpg)
Show that the roots of the equation 16x^4 - 20x^2 + 5= 0 are cos((kx)/10) for k = 1,3,7 and 9 And Deduce that cos^2(pi/10)cos^2((3pi)/10) = 5/16? | Socratic
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Amazon.com: MakerFocus Raspberry Pi 4 Camera Night Vision Camera Adjustable-Focus Module 5MP OV5647 Webcam Video 1080P Compatible with Raspberry Pi 3 B+/3B/2B+ : Electronics
![If sin A = 4/5,pi/2<A<pi and cos B = 5/13,3pi/2<B<2pi , find (i) sin (A + B) , (ii) cos (A - B) , (iii) tan (A - B) If sin A = 4/5,pi/2<A<pi and cos B = 5/13,3pi/2<B<2pi , find (i) sin (A + B) , (ii) cos (A - B) , (iii) tan (A - B)](https://dwes9vv9u0550.cloudfront.net/images/4437113/361c8f4e-203a-4149-942d-29d5ac362c6c.jpg)
If sin A = 4/5,pi/2<A<pi and cos B = 5/13,3pi/2<B<2pi , find (i) sin (A + B) , (ii) cos (A - B) , (iii) tan (A - B)
![If 4cos^(2)theta=3 then theta=---- 1) (pi)/(6),(5 pi)/(6) 2) (pi)/(4),(3 pi )/(4) 3) (pi)/(3),(2 pi)/(3) 4) +-(pi)/(2) If 4cos^(2)theta=3 then theta=---- 1) (pi)/(6),(5 pi)/(6) 2) (pi)/(4),(3 pi )/(4) 3) (pi)/(3),(2 pi)/(3) 4) +-(pi)/(2)](https://d10lpgp6xz60nq.cloudfront.net/web-thumb/469760544_web.png)