Answer:
C. 468mm²
Step-by-step explanation:
The formula for the surface area of rectangular prism is:
Let's break down our variables.
L = 12mm
W = 6mm
H = 7mm + 2mm = 9mm
Now we substitute our values in the formula:
Answer:
y = 3sin2t/2 - 3cos2t/4t + C/t
Step-by-step explanation:
The differential equation y' + 1/t y = 3 cos(2t) is a first order differential equation in the form y'+p(t)y = q(t) with integrating factor I = e^∫p(t)dt
Comparing the standard form with the given differential equation.
p(t) = 1/t and q(t) = 3cos(2t)
I = e^∫1/tdt
I = e^ln(t)
I = t
The general solution for first a first order DE is expressed as;
y×I = ∫q(t)Idt + C where I is the integrating factor and C is the constant of integration.
yt = ∫t(3cos2t)dt
yt = 3∫t(cos2t)dt ...... 1
Integrating ∫t(cos2t)dt using integration by part.
Let u = t, dv = cos2tdt
du/dt = 1; du = dt
v = ∫(cos2t)dt
v = sin2t/2
∫t(cos2t)dt = t(sin2t/2) + ∫(sin2t)/2dt
= tsin2t/2 - cos2t/4 ..... 2
Substituting equation 2 into 1
yt = 3(tsin2t/2 - cos2t/4) + C
Divide through by t
y = 3sin2t/2 - 3cos2t/4t + C/t
Hence the general solution to the ODE is y = 3sin2t/2 - 3cos2t/4t + C/t
Answer:
11. -2
12. +0.5
Step-by-step explanation:
11. as x increases by 1, y decreases by 2, -2/1 = -2 the ROC is -2 (rate of change)
12. as x increases by 2, y increases by 1, 1/2 = 0.5, ROC is +0.5
Point t slope form:
y + y value = m (x + x value) where m is the gradient
Parallel line must have the same gradient as the two lines never meet, so the gradient must be 4. This eliminates option B and D.
Remember that point-slope form is still an equation, so the values of both sides must be equal. So let's substitute the given coordinates.
Option A:
y-6=4(x+2)
-6-6 (-12) does not equal to 4(-2+2) (0)
Option C:
y+6=4(-2+2)
-6+6 (0) = 4(-2+2) (0)
Therefore, option C is your answer.
