Question

Heya Mate ....


Prove that


$\sin90 = 1 \\ \\ class \: 9$
​

Answer 1

Answer:

Step-by-step explanation:

We know that:

Sin(2A)=2Sin(A)Cos(A)

Let 2A=90,

=> A=45.

Substituting it into the above equation:

=>Sin(2*45)=2Sin(45)Cos(45)

=>Sin(90)=2Sin(45)Cos(45).

Taking RHS:

2Sin(45)Cos(45)

=>2*1/2

=>1.

Answer 2

Answer

SINCE,

SIN(2A)=2SIN(A)COS(A)

THEN,

LET US ASSUME 2A=90

->A=45

SUBSTITUTING,

SIN(2*45)=2SIN(45)COS(45)

SIN(90)=2SIN(45)COS(45)

TAKING RHS,

2SIN(45)COS(45)

->2*1/2

->1

HENCE, SIN 90=1

➡️HENCE PROVED.....