Free help with homework

Why join Brainly?

  • ask questions about your assignment
  • get answers with explanations
  • find similar questions


  • JNZ
  • Ambitious
we can also write it as 90*2-30
we have formula cos(90*n+or-★)
★ as thita
if n is odd digit then cos(90*n+or-★)=sin★
we have to check sin is in which quadrant and take value +ve or -ve
if n is even the value is cos★ just like sine
here n is even and★ is in II quadrant
hence cos( 90*2-30 )=-cos30=-√3/2

hope i have helped you
0 0 0
The Brain
  • The Brain
  • Helper
Not sure about the answer?
Learn more with Brainly!
Having trouble with your homework?
Get free help!
  • 80% of questions are answered in under 10 minutes
  • Answers come with explanations, so that you can learn
  • Answer quality is ensured by our experts