Question

8. The value of sin 60° cos 30° + sin 30° cos 60° is:

(a)0

(b)1

(c)2

(d)4

Answer 1

8. The value of sin 60° cos 30° + sin 30° cos 60° is:

(a)0

(b)1

(c)2

(d)4

Answer: b

Explanation: sin 60° = √3/2, sin 30° = ½, cos 60° = ½ and cos 30° = √3/2

Therefore,

√3/2 x √3/2 + ½ x ½

= 3/4 + 1/4

= 1

Answer 2

Answer:

$\huge\boxed{1}$

Step-by-step explanation:

$\huge\boxed{\underline{\underline{\mathsf{\red{QUESTION}}}}}$

$\mathsf{\underline{\star{The \:value\: of\:( sin 60° cos 30° + sin 30° cos 60°) is}}}$

$\huge\boxed{\underline{\underline{\mathsf{\red{SOLUTION}}}}}$

$\mathbf{We\; know \:that:}\\\mathbf{sin60 = \frac{ \sqrt{3} }{2} \:cos30 = \frac{ \sqrt{3} }{2} \:sin30 = \frac{1}{2}\:cos60 = \frac{1}{2} }$

$\frac{ \sqrt{3} }{2} \times \frac{ \sqrt{3} }{2} + \frac{1}{2} \times \frac{1}{2} = \frac{3}{4} + \frac{1}{4} = \frac{4}{4}$

$\huge\boxed{\mathbf{In\:another\:method}}$

$\huge\boxed{\mathbf{\red{\underline{\underline{sinAcosB + sinBcosA = sin(A + B)}}}}}$

$\mathbf{sin(60 + 30) = sin90 = 1}$