Calculate 10^2 - 4*(-16)*(-20)
16x2 - 49 = 42x2 - 72 = (4x)2 - 72 = (4x - 7)(4x + 7)
4x times 4x equals 16x2.
Equals means=ok
y = -16x2 + 342At the x-intercepts, y=0-16x2 + 342 = 016x2 = 342x2 = 342/16 = 21.375x = plus and minus sqrt(21.375) = approx. plus and minus 4.6233 (rounded)
sqrt(10x)*sqrt(8x) = sqrt(80x2) = sqrt(16x2*5) = sqrt(16x2)*sqrt(5) = 4x*sqrt(5)
If you can't factor it easily, use the quadratic formula.
16x2 + 8x + 1 = 0 : This factorises to (4x + 1)(4x + 1) = 0 When 4x + 1 = 0 then 4x = -1 : x = -1/4.
4X = 16X2 4X - 16X2 = 0 (1 - 4X)4X = 0 ------------------ as you see X = 0 -------- 1 - 4X = 0 - 4X = - 1 X = 1/4 ----------- So, X = 0 and X = 1/4. You check.
The derivative of y=arcsin(4x) is dy/dx = 4/sqrt(1-16x2).
The value of 64x3 + 27 depends on the value of x. If the question required factorisation, but did not ask for it, the answer is: (4x + 3)(16x2 - 12x + 9)
It is: 4-16x2 = (2-4x)(2+4x) when factored
You double the product of 2x8.2x8 equals 16. 16 doubled which equal 16x2 equals 32.4x8 equals 32.