# physics

1) y=4+5x + 7x³. Find dy/dx
2) if y= tan x cos²x then dy by dx will be-

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1. 1) 0 + 5 + 21 x^2

2) tan x (d cos^2 x /dx)+ cos^2 x d tan x / dx

= tan x (-2 sin x cos x) + cos^2 x (sec^2 x)

= -2 sin^2 x + 1

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posted by Damon

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