Answer:
Part A: yes
Part B: yes
Part C: yes
Step-by-step explanation:
Part A:
77² + 420² = 427²
5,929 + 176,400 = 182,329
182,329 = 182,329
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Part B:
279² + 440² = 521²
77,841 + 193,600 = 271,441
271,441 = 271,441
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Part C:
39² + 760² = 761²
1,521 + 577,600 = 579,121
579121 = 579,121
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Answer: 9
Step-by-step explanation:

<span>we know that cos(a - b) = cos(a) cos(b) + sin(a) sin(b)
given a = π/3 and b = π/5
cos(π/3) cos(π/5) + sin(π/3) sin(π/5) = cos((π/3) - (π/5) = cos(2π/15)
hope it helps
</span>
Answer: of whattt???
Step-by-step explanation: