本文主要通过函数和求导规则,介绍函数y=23x^2+21x+arcsin8.x的一阶、二阶和三阶导数计算步骤。
方法/步骤
1、对y=23x^3+21x+arcsin8/x求一阶导数,有:
dy/dx=23*3x^2+21+(8/x)’/√[1-(8/x)^2]
=23*3x^2+21+(-8/x^2)/√[1-(8/x)^2]
=69x^2+21-8/[x√(x^2-64)]。
2、对dy/dx=69x^2+21-8/[x√(x^2-64)]
继续对x求导有:
dy^2/dx^2
=69*2x+8*[√(x^2-64)+x*2x]/[x^2(x^2-64)]
=138x+8*[√(x^2-64)+2x^2]/[x^2(x^2-64)]
3、三阶导数计算
∵dy^2/dx=138x+8*[√(x^2-64)+2x^2]/[x^2(x^2-64)],
∴dy^3/dx^3
=138+8*{[x/√(x^2-64)+4x][x^2(x^2-64)]-[√(x^2-64)+2x^2](4x^3-2*64x)}/[x^4(x^2-64)^2]
=138+8*{[1/√(x^2-64)+4][x^2(x^2-64)]-2[√(x^2-64)+2x^2](2x^2-64)}/[x^3(x^2-64)^2]
=138+8*{[1+4√(x^2-64)][x^2(x^2-64)]-2[(x^2-64)+2x^2*√(x^2-64)](2x^2-64)}/[x^3*√(x^2-64)^5]
4、=138+8*[(x^2-64)(2*64-3x^2)-4x^2*√(x^2-64)]/[x^3*√(x^2-64)^5]
=138+8*[(2*64-3x^2)*(x^2-64)-4x^4*√(x^2-64)]/[x^3*√(x^2-64)^5]
=138+8*[(2*64-3x^2)*√(x^2-64)-4x^4]/[x^3*(x^2-64)^2]。
本文来自于百度作者:吉禄学阁,仅代表原作者个人观点。本站旨在传播优质文章,无商业用途。如不想在本站展示可联系删除