3
=∫ √2 − − 2 2 : 2 − − 2 = −( 2 + − 2) = − [( 2 +2( 1 2 )+ 1 4 )− 1 4 − 2] = − [( + 1 2 ) 2 9 4 ]= 9 4 − ( + 1 2 ) 2 =∫ 9 4 − ( + 1 2 ) 2 2 1: = + 1 2 ; = ; = − 1 2 =∫ 9 4 2 ( − 1 2 ) 2 : = 3 2 ; = 3 2 ; => 9 4 2 = 9 4 2 =∫ 9 2 4( 3 2 1 2 ) 2 = 9 4 2 (3 − 1) 2 4 = 9 ∫ 2 (3 − 1) 2 = ; = − ; = (3 − 1) 2 =∫ (3 − 1) 2 = − 1 3(3 − 1) + =9∫ 2 (3 − 1) 2 = − 3(3 − 1) −∫ 3(3 − 1) =9∫ 2 (3 − 1) 2 = − 3(3 − 1) 1 3 [ 1 3 3 − 1 + 1 (3 − 1) ] =9∫ 2 (3 − 1) 2 = − 3(3 − 1) 1 9 [∫ 3 − 1 (3 − 1) + ∫ 1 (3 − 1) ] =9∫ 2 (3 − 1) 2 = − 3(3 − 1) 1 9 [∫ + ∫ 1 (3 − 1) ] =∫ 2 (3 − 1) 2 = − 3 (3 − 1) − [ + ∫ 1 (3 − 1) ]

Integral 31

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𝐼 = ∫√2 − 𝑥 − 𝑥2

𝑥2𝑑𝑥

𝐶𝑜𝑚𝑝𝑙𝑒𝑡𝑎𝑛𝑑𝑜 𝑐𝑢𝑎𝑑𝑟𝑎𝑑𝑜𝑠: 2 − 𝑥 − 𝑥2 = −(𝑥2 + 𝑥 − 2) = − [(𝑥2 + 2(1

2)𝑥 +

1

4) −

1

4− 2]

= −[(𝑥 +1

2)2

−9

4] =

9

4− (𝑥 +

1

2)2

𝑆𝑢𝑠𝑡𝑖𝑡𝑢𝑦𝑒𝑛𝑑𝑜 𝑒𝑛 𝑙𝑎 𝐼𝑛𝑡𝑒𝑔𝑟𝑎𝑙

𝐼 = ∫√9

4− (𝑥 +

12)2

𝑥2𝑑𝑥

𝐻𝑎𝑐𝑖𝑒𝑛𝑑𝑜 𝑒𝑙 𝑐𝑎𝑚𝑏𝑖𝑜 𝑑𝑒 𝑣𝑎𝑟𝑖𝑎𝑏𝑙𝑒 1: 𝑦 = 𝑥 +1

2 ; 𝑑𝑦 = 𝑑𝑥 ; 𝑑𝑒 𝑑𝑜𝑛𝑑𝑒 𝑥 = 𝑦 −

1

2

𝐼 = ∫√9

4− 𝑦2

(𝑦 −12)2 𝑑𝑦

𝐴𝑝𝑙𝑖𝑐𝑎𝑚𝑜𝑠 𝑆𝑢𝑠𝑡𝑖𝑢𝑐𝑖𝑜𝑛 𝑡𝑟𝑖𝑔𝑜𝑛𝑜𝑚𝑒𝑡𝑟𝑖𝑐𝑎: 𝑦 =3

2𝑠𝑒𝑛𝜃 ; 𝑑𝑦 =

3

2𝑐𝑜𝑠𝜃𝑑𝜃 ;=>

9

4− 𝑦2 =

9

4𝑐𝑜𝑠2𝜃

𝐼 = ∫9𝑐𝑜𝑠2𝜃

4 (32 𝑠𝑒𝑛𝜃 −

12)

2 𝑑𝜃 =9

4∫

𝑐𝑜𝑠2𝜃

(3𝑠𝑒𝑛𝜃 − 1)2

4

𝑑𝜃 = 9∫𝑐𝑜𝑠2𝜃

(3𝑠𝑒𝑛𝜃 − 1)2𝑑𝜃

𝐴ℎ𝑜𝑟𝑎 𝑡𝑟𝑎𝑏𝑎𝑗𝑎𝑟𝑒𝑚𝑜𝑠 𝑝𝑜𝑟 𝑝𝑎𝑟𝑡𝑒𝑠

𝑠𝑒𝑎 𝑢 = 𝑐𝑜𝑠𝜃 ; 𝑑𝑢 = −𝑠𝑒𝑛𝜃𝑑𝜃 ; 𝑑𝑣 =𝑐𝑜𝑠𝜃

(3𝑠𝑒𝑛𝜃 − 1)2𝑑𝜃

𝑣 = ∫𝑐𝑜𝑠𝜃

(3𝑠𝑒𝑛𝜃 − 1)2𝑑𝜃 = −

1

3(3𝑠𝑒𝑛𝜃 − 1)+ 𝑐

𝐼 = 9∫𝑐𝑜𝑠2𝜃

(3𝑠𝑒𝑛𝜃 − 1)2𝑑𝜃 = −

𝑐𝑜𝑠𝜃

3(3𝑠𝑒𝑛𝜃 − 1)− ∫

𝑠𝑒𝑛𝜃

3(3𝑠𝑒𝑛𝜃 − 1)𝑑𝜃

𝑀𝑎𝑛𝑖𝑝𝑢𝑙𝑎𝑚𝑜𝑠 𝑢𝑛 𝑝𝑜𝑐𝑜 𝑙𝑎 𝑖𝑛𝑡𝑒𝑔𝑟𝑎𝑙

𝐼 = 9∫𝑐𝑜𝑠2𝜃

(3𝑠𝑒𝑛𝜃 − 1)2𝑑𝜃 = −

𝑐𝑜𝑠𝜃

3(3𝑠𝑒𝑛𝜃 − 1)−

1

3[1

3∫

3𝑠𝑒𝑛𝜃 − 1 + 1

(3𝑠𝑒𝑛𝜃 − 1)𝑑𝜃]

𝐼 = 9∫𝑐𝑜𝑠2𝜃

(3𝑠𝑒𝑛𝜃 − 1)2𝑑𝜃 = −

𝑐𝑜𝑠𝜃

3(3𝑠𝑒𝑛𝜃 − 1)−

1

9[∫

3𝑠𝑒𝑛𝜃 − 1

(3𝑠𝑒𝑛𝜃 − 1)𝑑𝜃 + ∫

1

(3𝑠𝑒𝑛𝜃 − 1)𝑑𝜃]

𝐼 = 9∫𝑐𝑜𝑠2𝜃

(3𝑠𝑒𝑛𝜃 − 1)2𝑑𝜃 = −

𝑐𝑜𝑠𝜃

3(3𝑠𝑒𝑛𝜃 − 1)−

1

9[∫𝑑𝜃 + ∫

1

(3𝑠𝑒𝑛𝜃 − 1)𝑑𝜃]

𝐼 = ∫𝑐𝑜𝑠2𝜃

(3𝑠𝑒𝑛𝜃 − 1)2𝑑𝜃 = −

3𝑐𝑜𝑠𝜃

(3𝑠𝑒𝑛𝜃 − 1)− [𝜃 + ∫

1

(3𝑠𝑒𝑛𝜃 − 1)𝑑𝜃]

𝑆𝑒𝑎 𝐴 = ∫1

(3𝑠𝑒𝑛𝜃 − 1)𝑑𝜃

𝑈𝑡𝑖𝑙𝑖𝑧𝑎𝑟𝑒𝑚𝑜𝑠 𝑒𝑙 𝑚𝑒𝑡𝑜𝑑𝑜 𝑑𝑒 𝐶𝑎𝑚𝑏𝑖𝑜 𝑈𝑛𝑖𝑣𝑒𝑟𝑠𝑎𝑙

𝑆𝑒𝑎 𝑡 = 𝑡𝑔 (𝜃

2) ; 𝑠𝑒𝑛𝜃 =

2𝑡

1 + 𝑡2 ; 𝑑𝜃 =

2

1 + 𝑡2𝑑𝑡

𝐴 = ∫1

(6𝑡

1 + 𝑡2 − 1)(

2

1 + 𝑡2)𝑑𝑡 = 2∫

1

(6𝑡 − 1 − 𝑡2)𝑑𝑡

𝐶𝑜𝑚𝑝𝑙𝑒𝑡𝑎𝑚𝑜𝑠 𝑐𝑢𝑎𝑑𝑟𝑎𝑑𝑜𝑠 𝑒𝑛 𝑒𝑙 𝑑𝑒𝑛𝑜𝑚𝑖𝑛𝑎𝑑𝑜𝑟

(6𝑡 − 1 − 𝑡2) = −(𝑡2 − 6𝑡 + 1) = −[(𝑡2 − 2(3)𝑡 + 9) − 9 + 1] = −[(𝑡 − 3)2 − 8] = 8 − (𝑡 − 3)2

𝑆𝑢𝑠𝑡𝑖𝑡𝑢𝑖𝑚𝑜𝑠 𝑒𝑛 𝐴

𝐴 = 2∫1

8 − (𝑡 − 3)2𝑑𝑡

𝐻𝑎𝑐𝑒𝑚𝑜𝑠 𝑆𝑢𝑠𝑡𝑖𝑡𝑢𝑐𝑖𝑜𝑛 𝑇𝑟𝑖𝑔𝑜𝑛𝑜𝑚𝑒𝑡𝑟𝑖𝑐𝑎: (𝑡 − 3) = √8𝑠𝑒𝑛𝛿 ; 𝑑𝑡 = √8𝑐𝑜𝑠𝛿𝑑𝛿 ; 8 − (𝑡 − 3)2 = 8𝑐𝑜𝑠2𝛿

𝐴 = 2∫√8𝑐𝑜𝑠𝛿𝑑𝛿

8𝑐𝑜𝑠2𝛿=

√8

4∫𝑠𝑒𝑐𝛿𝑑𝛿 =

√8

4𝐿𝑛|𝑠𝑒𝑐𝛿 + 𝑡𝑔𝛿| + 𝐶

𝑠𝑒𝑛𝛿 =𝑡 − 3

√8 ; 𝑠𝑒𝑐𝛿 =

√8

√8 − (𝑡 − 3)2 ; 𝑡𝑔𝛿 =

𝑡 − 3

√8 − (𝑡 − 3)2

𝐴 =√8

4𝐿𝑛 |

√8

√8 − (𝑡 − 3)2+

𝑡 − 3

√8 − (𝑡 − 3)2| + 𝑐 =

√8

4𝐿𝑛 |

√8 + 𝑡 − 3

√6𝑡 − 1 − 𝑡2|

𝐷𝑒𝑣𝑜𝑙𝑣𝑖𝑒𝑛𝑑𝑜 𝑒𝑙 𝐶𝑎𝑚𝑏𝑖𝑜 𝑈𝑛𝑖𝑣𝑒𝑟𝑠𝑎𝑙:

𝐴 =√8

4𝐿𝑛 ||

√8 + 𝑡𝑔 (𝜃2) − 3

√6𝑡𝑔 (𝜃2) − 1 − 𝑡𝑔2 (

𝜃2)

|| + 𝐶

𝐸𝑛𝑡𝑜𝑛𝑐𝑒𝑠:

𝐼 = −3𝑐𝑜𝑠𝜃

(3𝑠𝑒𝑛𝜃 − 1)−

[

𝜃 +√8

4𝐿𝑛 ||

√8 + 𝑡𝑔 (𝜃2) − 3

√6𝑡𝑔 (𝜃2) − 1 − 𝑡𝑔2 (

𝜃2)

||

]

+ 𝐶

𝐷𝑒𝑣𝑜𝑙𝑣𝑖𝑒𝑛𝑑𝑜 𝑒𝑙 1𝑒𝑟 𝐶𝑎𝑚𝑏𝑖𝑜 𝑇𝑟𝑖𝑔𝑜𝑛𝑜𝑚𝑒𝑡𝑟𝑖𝑐𝑜:

𝑠𝑒𝑛𝜃 =𝑦

(32) ; 𝑐𝑜𝑠𝜃 =

2√94 − 𝑦2

3 ; 𝜃 = 𝐴𝑟𝑐𝑠𝑒𝑛 (

2𝑦

3)

𝐼 = −2√9

4 − 𝑦2

(2𝑦 − 1)−

[

𝐴𝑟𝑐𝑠𝑒𝑛 (2𝑦

3) +

√8

4𝐿𝑛

|

|

| √8 + 𝑡𝑔 (𝐴𝑟𝑐𝑠𝑒𝑛 (

2𝑦3

)

2 ) − 3

√6𝑡𝑔(𝐴𝑟𝑐𝑠𝑒𝑛 (

2𝑦3 )

2) − 1 − 𝑡𝑔2 (

𝐴𝑟𝑐𝑠𝑒𝑛 (2𝑦3 )

2)|

|

|

]

+ 𝑐

𝐷𝑒𝑣𝑜𝑙𝑣𝑖𝑒𝑛𝑑𝑜 𝑒𝑙 𝑐𝑎𝑚𝑏𝑖𝑜 1: 𝑦 = 𝑥 +1

2

𝐼 = −2√2 − 𝑥 − 𝑥2

2𝑥−

[

𝐴𝑟𝑐𝑠𝑒𝑛 (2𝑥 + 1

3) +

√8

4𝐿𝑛

|

|

| √8 + 𝑡𝑔 (𝐴𝑟𝑐𝑠𝑒𝑛 (

2𝑥 + 13 )

2 ) − 3

√6𝑡𝑔(𝐴𝑟𝑐𝑠𝑒𝑛 (

2𝑥 + 13 )

2 ) − 1 − 𝑡𝑔2 (𝐴𝑟𝑐𝑠𝑒𝑛 (

2𝑥 + 13 )

2 )|

|

|

]

+ 𝑐

𝑭𝑰𝑵𝑨𝑳𝑰𝒁𝑨𝑵𝑫𝑶:

𝐼 = ∫√2 − 𝑥 − 𝑥2

𝑥2𝑑𝑥 = −

√2 − 𝑥 − 𝑥2

𝑥− 𝐴𝑟𝑐𝑠𝑒𝑛 (

2𝑥 + 1

3) −

√8

4𝐿𝑛

|

|

| √8 + 𝑡𝑔 (𝐴𝑟𝑐𝑠𝑒𝑛 (

2𝑥 + 13

)

2) − 3

√6𝑡𝑔 (𝐴𝑟𝑐𝑠𝑒𝑛 (

2𝑥 + 13 )

2) − 1 − 𝑡𝑔2 (

𝐴𝑟𝑐𝑠𝑒𝑛 (2𝑥 + 1

3 )

2)|

|

|

+ 𝐶