Tải bản đầy đủ (.pdf) (3 trang)

Bài tập CALCULUS 58

Bạn đang xem bản rút gọn của tài liệu. Xem và tải ngay bản đầy đủ của tài liệu tại đây (926.21 KB, 3 trang )

Created by T. Madas
Question 203

(****)
y
y = 1 x2 − 2 x + 6
2

P
L1

R

Q

L2
O

x

The figure above shows the graph of the curve C with equation

y = 1 x2 − 2 x + 6 .
2
The point P is the point where C meets the y axis so that the straight line L1 is the
normal to C at P .

a) Find an equation for L1 .

( )


The point Q 3, 9 lies on C and the straight line L2 is the normal to C at Q .
2
The finite region R , shown shaded in the figure above, is bounded by L1 , L2 and C .

b) Find the area of R .

SYN-J , y = 1 x + 6 , 15
4
2

Created by T. Madas


Created by T. Madas
Question 204

(****)

6x

L
8x

The figure above shows a triangular prism with a volume of 960 cm3 .
The triangular faces of the prism are right angled with a base 8 x cm and a height of
6 x cm . The length of the prism is L cm .

a) Show that the surface area of the prism, A cm 2 , is given by

A = 48 x 2 +


960
.
x

b) Determine an exact value of x for which A is stationary and show that this
value of x minimizes A .
c) Show further that the minimum surface area of the prism is 144 3 100 cm 2 .
SYN-Z , x = 3 10 ≈ 2.15

Created by T. Madas


Created by T. Madas
Question 205

(****) non calculator

y=

Show that the value of

d2y
dx

2

1 2

 − 3 , x ∈ » , x > 0 .

3 xx


where x = 2 , is

2
.
16
proof

Created by T. Madas



Tài liệu bạn tìm kiếm đã sẵn sàng tải về

Tải bản đầy đủ ngay
×