  A classically scale invariant (CSI) extension of the standard model (SM)
induces radiative electroweak symmetry breaking and predicts anomalously large
Higgs self-interactions. Hence, $W_LW_L$ scattering processes can be a good
probe of the symmetry breaking mechanism. We develop a theoretical framework
for perturbative computation and calculate $WW$ scattering amplitudes in a CSI
model. It is shown that $W_LW_L$ scattering amplitudes satisfy the equivalence
theorem, and that a large deviation of $W_LW_L$ differential cross sections
from the SM predictions is predicted depending on the c.m. energy and
scattering angle. The results are more accurate than those based on the
effective-potential approach. A prescription to implement predictions of the
CSI model to Monte Carlo event generators is also presented.
