answer: (6-x^2)/ 2sqrt(x)(x^2+6)^(3/2)
answer: 9xsec sqrt(9x^2+7)^2 / sqrt(9x^2+7)
answer: okay this im unsure but ill show you the steps.
y = sin2x x = pi/4
f(x) = sin2(pi/4) = 1 this is y.
f'(x) = 2cos(2x) = 0 this is m
y = mx + b
1 = 0x + b
1 = b
y = mx + 1 <-- is this right?
answer: 5cos(8x^5) - 200x^5sin(8x^5)
the numbers im very unsure about are 3 & 5, i mightve screwed up a step(s). im pretty sure about #4 but is that a valid answer? just asking to check and not begging for answers.