Question

80cm3 into ml conversion ​

Answer 1

Answer:

π8+cos43π8+cos45π8+cos47π8 =cos4π8+cos43π8+cos4(π−3π8)+cos4(π−π8)

=2[(cos2π8+sin2π8)2−2sin2π8cos2π8]=2[1−2sin2π8cos2π8]=2−(sinπ4)2  =2−(1√2)2=2−12=32