Question

Ex. 7. Prove that
cos 11° + sin 11°
cos 11°-sin 11°
= tan 56°​

Answer 1

Answer:

So we are given  in the L.H.S. and tan 56 in the R.H.S.

So, let's start solving the question from the L.H.S.

Now, let's start by dividing the numerator and the denominator by cos 11.

Simplify.

Now as we know that "tan 45° = 1", we'll replace the 1 to tan 45°.

Now let's simplify.

Now let's put the value of a and b in the above equation;

tan (45° +11°) = tan (56°) = R.H.S.

                                Hence, Proved

HOPE IT HELPS U

PLZ MARK AS BRAINLYEST

Answer 2

cos 11 + sin 11 ÷

cos11 -sin 11

this is the L.H.S.

DIVIDING BOTH SIDES WITH cos 11

in the numerator :cos 11+sin11/cos 11

which is equal to. 1+sin11/cos11 =1+tan 11

in the denominator : cos11-sin11/cos11

=1-cos11/sin11

=1-tan11

so,1+tan11/1-tan11

tan 11 gets cancelled

so and is 1

next in the R.H.S.: tan 45 is 1

therefore it's proved