求不定積分∫1/(x^2+4)dx求高手解題要步驟謝謝

求不定積分∫1/(x^2+4)dx求高手解題要步驟謝謝

∫1/(x^2+4)dx
=1/4∫1/[1+(x/2)²;]dx
=1/2∫1/[1+(x/2)²;]d(x/2)
=1/2arctanx/2+c
暈,反正切函數求導公式你會吧?這個書上有公式的
∫1/(x^2+4)dx
=1/4∫1/[1+(x/2)²;]dx
=1/2∫1/[1+(x/2)²;]d(x/2)
=1/2arctanx/2+c
凑微分,和換元法人家兩個人都說了
三角代換
設x = 2 tan u
dx = 2 sec^2 u du
∫1/(x^2+4)dx
=∫2sec^2 u/(4sec^2 u)du
=(1/2)u + c
=(1/2)tan^-1(x/2)+ c
凑微分直接公式
∫1/(x^2+4)dx
=1/4∫1/[…展開
凑微分,和換元法人家兩個人都說了
三角代換
設x = 2 tan u
dx = 2 sec^2 u du
∫1/(x^2+4)dx
=∫2sec^2 u/(4sec^2 u)du
=(1/2)u + c
=(1/2)tan^-1(x/2)+ c
凑微分直接公式
∫1/(x^2+4)dx
=1/4∫1/[1+(x/2)²;]dx
=1/2∫1/[1+(x/2)²;]d(x/2)
=1/2arctanx/2+c收起
因式分解-ab(a-b)²;+a(b-a)²;-ac(a-b)²;=
首先要清楚(a-b)²;=(b-a)²;
所以上述式子選取公因式a(a-b)²;
得到a(a-b)²;*(-b+1-c)
求不定積分∫x^2/[√(2-x)]dx的詳細解題步驟
設√(2-x)=t
x=2-t^2 dx=d(2-t^2)=-2tdt
代入
∫x^2/[√(2-x)]dx=∫(8t^2-2t^4-8)dt=(8/3)t^3-(2/5)t^5-8t+C
t=√(2-x)代入即可
分解因式:(x²;-2xy)²;+2y²;(x²;-2xy)+y^4
=(x²;-2xy+y²;)²;
=(x-y)的4次方
正確答案(x-y)^4
求不定積分∫dx/(1+x^1/2)
令√x=t
x=t^2
dx=2tdt
∫dx/(1+x^1/2)
=∫1/(1+t)*2tdt
=2∫[1-1/(1+t)]dt
=2t-2ln(1+t)+C
自己反代吧
x²;-2xy+y²;+2x-2y+1分解因式
x²;-2xy+y²;+2x-2y+1分解因式
=(x-y)²;+2(x-y)+1
=[(x-y)+1]²;
=(x-y+1)²;;
很高興為您解答,skyhunter002為您答疑解惑
如果本題有什麼不明白可以追問,
x²;-2xy+y²;+2x-2y+1
=(x-y)²;+2(x-y)+1
=(x-y+1)²;
x²;-2xy+y²;+2x-2y+1分解因式
=(x-y)²;+2(x-y)+1
=[(x-y)+1]²;
=(x-y+1)²;;恩恩,很高興幫你解答,祝你事事如願,天天快樂哈
求定積分(下限0,上限π/4)∫(1/(1+(cosx)^2))dx
分解因式:y(y+1)(x²;+1)+x(2y²;+2y+1)
y(y+1)(x²;+1)+x(2y²;+2y+1)
=y(y+1)x²;+(2y²;+2y+1)x+y(y+1)
=(yx+y+1)[(y+1)x+y]
=(xy+y+1)(xy+x+y)
求定積分[上限π,下限0]∫(x^2)sgn(cosx)dx
[0,Pi/2]的時候
sgn(cosx)= 1
[Pi/2,Pi]的時候
sgn(cosx)= -1
所以
∫(x^2)sgn(cosx)dx
=∫[0,Pi/2](x^2)dx-∫[Pi/2,Pi](x^2)dx
=Pi^3/24 - Pi^3/3 + Pi^3/24
=-Pi^3/4
∫(0,π)(x^2)sgn(cosx)dx=∫(0,π/2)(x^2)dx-∫(π/2,π)(x^2)dx=-(1/4)π^3
分解因式:x2-y2-2y-1=______.
x2-y2-2y-1,=x2-(y2+2y+1),=x2-(y+1)2,=(x+y+1)(x-y-1).