Question

Lt
1- cos x cos 2x cos 3x
sin? 2x
x0​

Answer 1

Answer:

lim

x→0

xtan4x

(1−cos2x)(3+cosx)

⇒

x×4x

(1−1+2sin

2

x)(3+cosx)

×(

tan4x

4x

)

⇒

4x

2

2sin

2

x

×(3+cosx)×1

⇒

2

1

(

x

sinx

)

2

×(3+cosx)×1

⇒

2

1

×4×1=2