Question

if cos (45 degree +X) =sin30degree then X=?
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Answer 1

Answer:

45 + x = 60

Calculate and you will get x.

Step-by-step explanation:

Answer 2

Step-by-step explanation:

Given:-

Cos (45°+X) = Sin 30°

To find:-

Find the value of X ?

Solution:-

Method-1:-

Given that :

Cos (45°+X) = Sin 30°

CoS (45°+X) = Sin (90°-60°)

We know that

Sin (90°-A) = Cos A

=> Cos (45°+X) = Cos 60°

=> 45°+X = 60°

=> X = 60° - 45°

=> X = 15°

Method -2:-

Given that :

Cos (45°+X) = Sin 30°

=> Cos (90°-(45°-X)= Sin 30°

We know that

Cos (90°-A) = Sin A

=> Sin (45°-X) = Sin 30°

=> 45°-X = 30°

=> X = 45°-30°

=> X = 15°

Answer:-

The value of X for the given problem is 15°

Check:-

If X = 15° then

LHS = Cos (45°+X)

=> Cos (45°+15°)

=> Cos 60°

=> 1/2

RHS =

Sin 30°

= 1/2

LHS= RHS is true for X = 15°

Used formulae:-

• Sin (90°-A) = Cos A
• Cos (90°-A) = Sin A
• Cos 60° = 1/2
• Sin 30°= 1/2