Prove that:
Sin^2A+Sin^2B. Cos2A=Sin^2B+Sin^2A. Cos2B​

See Below.

Step-by-step explanation:

We want to prove that:

Recall that double-angle identity for cosine:

Substitute cos(2A) for its third form:

Distribute:

Rewrite:

Factor:

Double-Angle Identity for cosine:

Hence proven.

$320 to $405

step by step explanation:

in one day he earns between $64 and $81

therefore if he works for 5 days, he will earn between 64 x 5 to 81 x 5

= $320 to $405