Which expression is equivalent to cos120°? ° cos240° cos300° cos420°?

Option 1 - cos 240°

Step-by-step explanation:

Given : Expression

To find : Which expression is equivalent to given expression ?  

Solution :

The given  expression is equivalent to those whose value is same as

Value of

value of cos in second quadrant is negative.

Option 1 :

Equivalent

Option 2 :

Not equivalent

Option 3 :

Not equivalent

Therefore, Correct option is 1.

Correct option is 1.

Step-by-step explanation:

We have to find the expression which is equivalent to cos 120°

Expression:

The given expression is equivalent to those whose value is same as

value of cos 120° in second quadrant is negative.

Option 1 :

Value is same i.e equivalent

Option 2 :

Not equivalent

Option 3 :

Not equivalent

∴ Correct option is 1.

sites:

7.3

step-by-step explanation: