Verify the identity.cos 3x = cos3 x - 3 sin2 x cos x
What will be an ideal response?
cos 3x = cos (2x + x) = cos 2x cos x - sin 2x sin x = 
= 
= cos3 x - 3 sin2 x cos x.
You might also like to view...
Solve the problem.To the nearest dollar, the average tuition at a public four-year college was 
the year Jane enrolled there and 
when her sister began college 2 years later. Find, to the nearest dollar per year, the rate at which tuition was increasing.
A. $118 per year B. $124 per year C. $107 per year D. $128 per year
Factor completely. If a polynomial cannot be factored, say it is prime.x3 - 512
A. (x + 512)(x + 1)(x - 1) B. (x - 8)(x2 + 64) C. (x + 8)(x2 - 8x + 64) D. (x - 8)(x2 + 8x + 64)
Solve.The circumference of a circle C is directly proportional to its radius r. If the circumference of a circle whose radius is 6 feet is 12? feet, what is the circumference of a circle whose radius is 12 feet?
A. 12 + 6? feet B. 24? feet C. 24 feet D. 6? feet
Find the discount date and net payment date. (The net payment date is 20 days after the final discount date.)Invoice date: Nov 7Terms: 3/15 ROGGoods received: Dec 13
A. Discount date: Dec 15; net payment date: Jan 15 B. Discount date: Dec 28; net payment date: Jan 17 C. Discount date: Jan 7; net payment date: Jan 30 D. Discount date: Dec 28; net payment date: Jan 18