计算方法实验报告附件.docVIP

《计算方法》实验报告(附件) 专业及班级:机械0710 姓名：张玉成 学号：U200710821 日期：2009.11.28 1.用牛顿迭代法求解下列方程的正根 log(1+x)-x^2=0 x=0.3696 运行结果： 输入： Newt_1(shiyan1_1,1) 显示： k= 1,x=6.10253e-001,y=-6.98970e-001,yd=-1.79339e+000 k= 2,x=4.38135e-001,y=-1.65515e-001,yd=-9.61634e-001 k= 3,x=3.79770e-001,y=-3.41626e-002,yd=-5.85330e-001 k= 4,x=3.70078e-001,y=-4.41870e-003,yd=-4.55917e-001 k= 5,x=3.69589e-001,y=-2.12618e-004,yd=-4.34323e-001 k= 6,x=3.69576e-001,y=-5.72632e-006,yd=-4.33231e-001 k= 7,x=3.69575e-001,y=-1.47599e-007,yd=-4.33202e-001 Final answer=3.695753e-001 ans =0.3696 e^x-5x^2 =0 x=4.7079 运行结果： 输入：Newt_1(shiyan1_2,5) 显示： k= 1,x=4.76376e+000,y=2.34132e+001,yd=9.91077e+001 k= 2,x=4.71070e+000,y=3.71870e+000,yd=7.00861e+001 k= 3,x=4.70797e+000,y=1.76539e-001,yd=6.45306e+001 k= 4,x=4.70794e+000,y=1.76647e-003,yd=6.42528e+001 k= 5,x=4.70794e+000,y=1.39489e-005,yd=6.42500e+001 Final answer=4.707938e+000 ans =4.7079 x^3+2x-1=0 x=0.4534 运行结果： 输入：Newt_1(shiyan1_3,1) 显示： k= 1,x=6.02394e-001,y=2.00000e+000,yd=5.03010e+000 k= 2,x=4.66118e-001,y=4.23383e-001,yd=3.10681e+000 k= 3,x=4.53549e-001,y=3.35069e-002,yd=2.66588e+000 k= 4,x=4.53398e-001,y=3.95932e-004,yd=2.63083e+000 k= 5,x=4.53398e-001,y=2.09360e-006,yd=2.63041e+000 Final answer=4.533977e-001 ans =0.4534 (x+2)-x=0 x=2.0000 运行结果： 输入：Newt_1(shiyan1_4,1) 显示： k= 1,x=2.02879e+000,y=7.32051e-001,yd=-7.11565e-001 k= 2,x=2.00002e+000,y=-2.16052e-002,yd=-7.51049e-001 k= 3,x=2.00000e+000,y=-1.72788e-005,yd=-7.50157e-001 k= 4,x=2.00000e+000,y=-3.60276e-009,yd=-7.50156e-001 Final answer=2.000000e+000 ans =2.0000 2.先用图解法确定初始点，然后再求方程x sin x ?1 = 0 x ∈[0,10]的所有根。 y1=x.*sin(x); y2=1; 图形： 运行结果： 输入：Newt_1(shiyan2,1) 显示： k= 1,x=1.11463e+000,y=-1.58529e-001,yd=1.38292e+000 k= 2,x=1.11416e+000,y=6.61864e-004,yd=1.38810e+000 k= 3,x=1.11416e+000,y=-3.24115e-007,yd=1.38817e+000 Final answer=1.114157e+000 ans =1.1142 输入：Newt_1(shiyan2,3) 显示：k= 1,x=2.79702e+000,y=-5.76640e-001,yd=-2.84083e+000 k= 2,x=2.77312e+000,y=-5.51756e-0