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.

solution:

→c= a b , that is product of a and b is possible only when when a is m × n matrix and b is n × p matrix.

that is, number of columns of a= number of rows of b.

so, size of matrix , c= a b is , if a = (m × n)matrix

b= (n × p)matrix

then a b = [ (m × n)matrix] ×[   (n × p)matrix ]

→→c= a b= [m × p ] matrix

→→size of product a b will be equal to = number of rows of a × number of columns of b