2.75! Good luck hope you do good
Rewrite <span>2cos x + 1 = 0 as:
2 cos x = -1, and then cos x = -1/2
x must be in Quadrant II or Quadrant III, since the adj. side is negative.
Note that the angle 120 has adj. side -1 and hyp 2. So 120 degrees is one solution.
Now what about a possible 2nd solution, to be found in Quadrant III? That would be -120 degrees, which has the same terminal line as does 240 degrees.
No soap.
So, the solution is 120 degrees.</span>
Answer:
10x² + 6x + 3xy + 3y - y²
Step-by-step explanation:
Each term in the second factor is multiplied by each term in the first factor, as shown
(2x + y)(5x - y + 3)
= 2x(5x - y + 3) + y(5x - y + 3) ← distributing
= 10x² - 2xy + 6x + 5xy - y² + 3y ( collect like terms )
= 10x² + 6x + 3xy + 3y - y²
Recall that the derivative of a constant is 0.