Solving Algebra: How do we go from 1 to 2?

  • Thread starter Thread starter jimmy42
  • Start date Start date
  • Tags Tags
    Algebra
AI Thread Summary
The discussion centers on a query about the transition from the first equation, 1 -x(t)= −Bω2 cos(ωt) −Cω2 sin(ωt), to the second equation, 2 - x(t)=−ω2 x(t). A participant suggests that the correct interpretation involves rewriting the first equation to show that 0 x(t) equals Bcos(ωt) + Csin(ωt). They clarify that the second equation represents the second derivative of x(t), denoted as x''(t), which equals -ω²x(t). The conversation highlights the importance of understanding the relationship between derivatives and the functions involved in algebraic expressions.
jimmy42
Messages
50
Reaction score
0
Hello,

I am having some problem with some algebra:

1 -x(t)= −Bω2 cos(ωt) −Cω2 sin(ωt)
2 - x(t)=−ω2 x(t)

Can someone explain how we went from 1 to 2?

Thanks.
 
Physics news on Phys.org
hello jimmy! :smile:

i'll guess that that should read …

0 x(t)= Bcos(ωt) + Csin(ωt)

1 x''(t)= -Bω2cos(ωt) - Cω2sin(ωt)

2 x''(t) = −ω2x(t) :wink:
 
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
Thread 'Variable mass system : water sprayed into a moving container'
Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
Back
Top