The following equality on page 121 of Grafakos' Modern Fourier Analysis is escaping me: $$\int\limits_Q A(y) \left[\Psi(2^jx - 2^jy) - \sum\limits_{|\beta|\leq k-1} \frac{\partial^\beta\Psi(2^jx)}{\beta!}(-2^jy)^\beta \right] \; dy = \int\limits_Q A(y) \left[ \sum\limits_{|\beta|=k} \frac{\partial^\beta\Psi(2^jx - 2^j\theta y)}{\beta!}(-2^jy)^\beta \right] \; dy$$.
Above, $A$ is an $L^q$-atom for $H^1$, $\Psi$ is radial Schwartz function compactly supported away from the origin in frequency (used in Littlewood-Paley decomp.), $Q$ is a cube centered at the origin containing the support of $A$, and $\theta$ is (apparently) any constant in $[0,1]$.
If anyone could provide any insight as to why this is true, that would be greatly appreciated. Thank you in advance!