xjai1ba
xiaiba

所有左点的数组所有右点的数组
fxjsubsfxxxj所有左点值
fxisubsfxxxi所有右点值
ffxifxj2ba
梯形面积
i
umsumf
加和梯形面积求解
i
tegratei
tfx12
i
tegratedoublei
tegrate
fpri
tfTherelativeerrorbetwee
i
uma
drealvalueisaboutg

absi
umi
tegratei
tegrate
【调试结果】i
um
069315152080005i
tegrate
069314718055995
Therelativeerrorbetwee
i
uma
drealvalueisabout626164e006

○2抛物线法：
抛物线法formatlo
g
120a1b2i
um0symsxfxfx1xfori1
xjai1ba
xiaiba
xkxixj2
左点右点中点
ffxjsubsfxxxjfxisubsfxxxifxksubsfxxxki
umi
umfxj4fxkfxiba6
e
di
umi
tegratei
tfx12i
tegratedoublei
tegratefpri
tfTherelativeerrorbetwee
i
uma
drealvalueisaboutg
absi
umi
tegratei
tegrate【调试结果】i
um
069314718056936
Therelativeerrorbetwee
i
uma
drealvalueisabout135886e011

○3使用函数trapz
x111202y1xtrapzxy
【调试结果】a
s
069315152080005
○4使用函数quad
quad1x12【调试结果】
a
s
069314719986297
2
○1使用函数trapz
x11120i
fysi
xxtrapzxy【调试结果】Errorusi
gcolo
Maximumvariablesizeallowedbytheprogramisexceeded
f○2使用函数quad
quadsi
xx0i
f【调试结果】a
s
NaN
○3程序法
矩阵法
formatlo
g

i
fa0bi
f
symsxfx
fxsi
xx
i1
xjai1ba
xiaiba

左点右点
xijxixj2fxjsubsfxxxjfxisubsfxxxifxijsubsfxxxij
左点值右点值中点值
f1fxjba

f2fxiba

f3fxijba

i
um1sumf1
i
um2sumf2
i
um3sumf3
i
tegratei
tfx0i
f
i
tegratedoublei
tegrate
fpri
tftherelativeerrorbetwee
i
um1a
drealvalueisaboutg

absi
um1i
tegratei
tegrate
fpri
tftherelativeerrorbetwee
i
um2a
drealvalueisaboutg

absi
um2i
tegratei
tegrate
fpri
tftherelativeerrorbetwee
i
um3a
drealvalueisaboutg

absi
um3i
tegratei
tegrate【调试结果】
Maximumvariablesizeallowedbytheprogramisexceeded
○4使用matlab命令
symsxfsi
xxIi
tf0i
f【调试结果】I
12pi
f3：
○1矩形法：利用求和函数
矩阵法
formatlo
g

100a0b1
symsxfx
fx11x2
i1
xjai1ba
xiaiba

左点右点
xijxixj2fxjsubsfxxxjfxisubsfxxxifxijsubsfxxxij
左点值右点值中点值
f1fxjba

f2fxiba

f3fxijba

i
um1sumf1
i
um2sumf2
i
um3sumf3
i
tegratei
tfx01
i
tegratedoublei
tegrate
fpri
tftherelativeerrorbetwee
i
um1a
drealvalueisaboutgr