math
NAME: ___________________________________________________________________ FINAL
Use SUBSTITUTION method to find the answers of the given integrals. To get full credit, you need to show U, dU/dx, and solve for dx, and substitution, and the process of substitution.
9. (5 points) A 10 feet long ladder that was leaning against the wall as shown below. A guy was pushing the lower end of the ladder toward the wall and his action made the top end of the ladder moving up against the wall at the rate of 4 feet per second. How fast was the lower end of the ladder moving toward the wall when the lower end was 8 feet away from the wall? and at the moment what was the rate of the area of the right triangle that was formed by the ladder with the wall and the ground was decreasing? (NOTE for full credit: label all sides as A= the wall, B = the ground and C = the ladder)
10.
(
)
2.lncos
y
axye
=
2.ln
sin
y
by
x
æö
=
ç÷
èø
(
)
5
3
3.311
axdx
-
ò
cos
3.
sin10
x
bdx
x
+
ò
ln(sin)
4.
tan
x
adx
x
ò
7
4.
(17)
x
x
e
bdx
e
+
ò
2
22
sec()
5.
tan()
ax
adx
aax
-
ò
72
35
5.
25(ln)
x
bdx
e
+
ò
6.
sin2sin3
Extendedsubstitution
xxdx
-
ò
2
7.
27
610
Thesplitmethod
x
dx
xx
+
++
ò
37
23
x
y
x
+
=
+
(
)
2
5
4
x
yx
=-+
2
45
yxx
=--
5
yx
=-
'
()
x
dy
ory
dx