A trig identity is <span>asinucosu=<span>a/2</span>sin(2u)</span>So you can write your equation as<span>y=sin(x)cos(x)=<span>1/2</span>sin(2x)</span>Use the crain rule here<span><span>y′</span>=<span>d/<span>dx</span></span><span>1/2</span>sin(2x)=<span>1/2</span>cos(2x)<span>d/<span>dx</span></span>2x=cos(2x)</span>The curve will have horizontal tangents when y' = 0.<span><span>y′</span>=0=cos(2x)</span>On the interval [-pi, pi], solution to that is<span><span>x=±<span>π4</span>,±<span><span>3π</span>4</span></span></span>
Answer:
B
Step-by-step explanation:
When you flip over the y-axis you the x is multiplied by -1
When the car is moving, it has Kinetic Energy. As soon as the car entercount with the spring, its Kinetic Energy will transfer to Elastic Potential Energy.
<span>KE = EPE </span>
<span>1/2mv^2 = 1/2kx^2 </span>
<span>change the speed into m/s </span>
<span>50 km/hr = 13.9 m/s </span>
<span>1/2(1200)(13.9)^2 = 1/2k(2.2)^2 </span>
<span>now you do the math to solve for k.
k= 115926/2.42
K= 47903.30</span>
